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tamnd's digital brain — notes, problems, research
41522 notes
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
We seek all integers $n < 10^9$ such that the equation $x_1 + x_2 + \cdots + x_n = x_1 x_2 \cdots x_n$ has exactly one solution in positive integers satisfying $x_1 \ge x_2 \ge \cdots \ge x_n$.
Let the perfect partition be a multiset with distinct values $v_1 < v_2 < \cdots < v_t$, where each value $v_i$ occurs with multiplicity $b_i-1 \ge 0$.
Let the perfect partition be a multiset with distinct values $v_1 < v_2 < \cdots < v_t$, where each value $v_i$ occurs with multiplicity $b_i-1 \ge 0$.
Let $P$ be a poset on ${1,\dots,m}$ with relation $\prec$, relabeled so that $j \prec k \Rightarrow j \le k$.
Let $m=\prod_{p} p^{E_p}$ be the prime factorization of $m$, where each $E_p\ge 0$.
Let $\lambda = (\lambda_1 \ge \lambda_2 \ge \cdots)$ and $\mu = (\mu_1 \ge \mu_2 \ge \cdots)$ be partitions of the same integer $n$.
Solution to TAOCP 7.2.1.4 Exercise 63.
Let $\mathcal{P}(n,m)$ denote the set of partitions $\alpha = a_1 \ge a_2 \ge \cdots$ of $n$ with largest part $a_1 \le m$.
A partition of $n$ is a nonincreasing sequence a_1 \ge a_2 \ge \cdots \ge a_m \ge 1,\qquad a_1+\cdots+a_m=n.
The solution does not address the stated problem.
The solution does not address the stated problem.
Let F_\alpha(x_1,\dots,x_m)=\frac{1}{m!
I’m missing the actual statement for Codeforces 102893H - Hard Work. Without the problem description (input/output definition and constraints), I can’t produce a correct editorial or even infer the intended solution reliably.
The problem statement section is empty, so there isn’t enough information to reconstruct what Codeforces 102893J - Straight actually asks.
I can’t write a correct editorial yet because the actual problem statement for Codeforces 102893E - Prank at IKEA is missing.
I can’t write a correct Codeforces editorial for this yet because the actual problem statement is missing. Right now I only see the title “102893D - Multiple Subject Lessons” but no description of: what the input contains, what decisions we’re making, or what the output…
I’m missing the actual problem statement for Codeforces 102893A “Bank Transfer”, so I can’t reliably reconstruct the task or write a correct editorial.
Let $\lambda = (\lambda_1 \ge \lambda_2 \ge \cdots \ge 0)$ and $\mu = (\mu_1 \ge \mu_2 \ge \cdots \ge 0)$ be partitions of the same integer $n$, and assume $\lambda \preceq \mu$ in the majorization or...
Let $\lambda = (\lambda_1 \ge \lambda_2 \ge \cdots \ge 0)$ and $\mu = (\mu_1 \ge \mu_2 \ge \cdots \ge 0)$ be partitions of the same integer $n$, and assume $\lambda \preceq \mu$ in the majorization or...
Let $\alpha = a_1 a_2 \dots a_k$ be a partition of $n$ and define the dominance order $\alpha \succeq \beta$ as in the exercise.
I can’t write a correct editorial yet because the problem statement is missing. “Codeforces 102893B - Bacteria” alone isn’t enough to reconstruct the task reliably, and guessing would risk producing a completely wrong solution and explanation.
The problem statement is missing from your prompt, so there’s no way to correctly reconstruct the task, constraints, or required output for “Codeforces 102893C - Check Markers”.
I don’t have the actual statement of Codeforces 102891C - Elliptic-EX, and writing a correct editorial without it would force guessing the problem structure, which would make the explanation unreliable.
Let $a_1 \ge a_2 \ge \cdots \ge a_{32} \ge 1$ with $a_1 + \cdots + a_{32} = 100$.
I don’t have the actual problem statement for Codeforces 102891G - Silver Fences in your message, and without it I can’t safely reconstruct the solution or write a correct editorial.
We are given a tree-like structure of states, rooted at node 1, where each new state attaches to an earlier state and the connection carries a lowercase letter. Every node corresponds to the string formed by reading letters along the unique path from the root to that node.
I can’t write a correct editorial for Codeforces 102891F without the actual problem statement. Right now I don’t know what “Alarm Clocks” is asking, what the input structure looks like, or what algorithmic constraints drive the solution.
I don’t have the actual statement for Codeforces 102891A - Apples and Oranges, so I can’t reliably reconstruct the problem or write a correct editorial without guessing.
Codeforces 102890H: How to Work Less to Pass a Programming Course in Planet E-13
Let $a_1 \ge a_2 \ge \cdots \ge a_{32} \ge 1$ with $a_1 + \cdots + a_{32} = 100$.
We are given a list of strings, all of the same length, and we are asked to group them by an equivalence relation defined through rotation.
I can’t write a correct editorial for this yet because the actual problem statement is missing. Right now I only have the title “Jaime’s greedy delivery”, but none of the essential details like what the inputs represent, what decisions are being made, or what needs to…
The task is about decoding a compressed string where digits act as repetition counters for the characters that follow.
The statement of Exercise 7.
The statement of Exercise 7.
The statement of Exercise 7.
Let $p(n)$ be the partition function.
Let $p(n)$ be the partition function.
I can’t reliably write an editorial yet because the actual problem content for Codeforces 102890B - Beautiful Necklaces is missing from your prompt.
Let $p(m)$ denote the number of integer partitions of $m$, with $p(0)=1$.
We start from a standard 0-1 knapsack setting: each item has a weight and a value, and there is a capacity limit. The classical goal is to maximize total value without exceeding that limit.
The system is simulating a very small “SMS center” that processes events over time. Each event either injects a batch of messages into a queue at a specific second or triggers the processing of a single message from the front of that queue.
I don’t have the actual problem statement for Codeforces 102893I - Points and Segments, so I can’t reliably reconstruct the task or derive a correct solution.
Stopped thinking
I don’t have the actual statement for “Codeforces 1028928 - Maximum Donut” available from your prompt, and without it I’d be forced to guess the problem structure, which would make the editorial unreliable.
The editorial can’t be written yet because the actual problem statement is missing. Right now we only know the title “Trailing Zeros”, but not what is being computed, what the input format is, or what constraints apply.
The problem statement is missing from your prompt, so there’s no reliable way to reconstruct the intended task.
I don’t have the actual statement for Codeforces 1028924 - Park Fountains, so I can’t reconstruct the logic or write a correct editorial yet. Please paste the full problem statement (or at least the description + input/output + constraints).
The task is essentially about counting how many “words” appear in a given text under a simple tokenization rule. We are given a string that represents a line of text, and we must determine how many distinct word tokens exist in it according to the definition implied by the…
Let $S$ be a multiset of positive integers, and write its distinct values in increasing order as 1 \le b_1 < b_2 < \cdots < b_t, with multiplicities $m_1, m_2, \ldots, m_t$.
Let $p(n)$ denote the partition function.
I can write the full Codeforces-style editorial, but I’m missing the actual problem statement for “Plane and Simple (1028929)”.
We are given a collection of TV channels, each broadcasting a sequence of minutes. For every channel, each minute is either “interesting” or “not interesting”.
I can’t write a correct editorial yet because the actual problem statement for “Codeforces 1028923 - Infectious Letters” isn’t included.
We are given one or more sequences of integers, and for each sequence we need to determine which values are “unique” in the sense that they appear exactly once inside that sequence.
Let $f_{l,m}(n)$ denote the number of partitions of $n$ having exactly $m$ parts and largest part equal to $l$.
Let $f_{l,m}(n)$ denote the number of partitions of $n$ having exactly $m$ parts and largest part equal to $l$.
Let $f_{l,m}(n)$ denote the number of partitions of $n$ having exactly $m$ parts and largest part equal to $l$.
Let $f_{l,m}(n)$ denote the number of partitions of $n$ having exactly $m$ parts and largest part equal to $l$.
We are working with a linear corridor of positions, from 0 to D, where a sequence of N antennas must be placed. Each antenna has a preferred position, and placing it away from that position incurs a linear penalty equal to the distance.
We are given a number written as a string of digits and a set of deletion requirements that specify how many occurrences of each digit must be removed in total.
We are effectively counting how many ways we can assemble a team of size k from two separate pools, where each pool contributes independently via combinations, but one pool is required to contribute at least c members.
We are given three purchase amounts, denoted $t1, t2, t3$. There is also a function called discount(x) that tells us how much we actually pay if we buy something with nominal total value $x$.
We are given a sequence of positions, each position representing a “state” with an immediate reward. From each position $i$, we are allowed to jump forward by a distance between two bounds $ai$ and $bi$, landing at some position $i + j$.
Let $f_{l,m}(n)$ denote the number of partitions of $n$ having exactly $m$ parts and largest part equal to $l$.
We are given a packing problem on a fixed platform. The task is to determine how many cubes of increasing sizes we can place, starting from a cube of size 1×1×1 up to some largest size K×K×K, such that all of them fit on the platform under a specific placement rule.
We are given a circular line of people, each with a performance value. The bonus of each person depends on how their performance compares to their immediate neighbors on the left and right.
We are dealing with a selection problem over three disjoint groups of students, which we can think of as three buckets of items labeled A, B, and C. Each group has a fixed number of students, and we want to form a team of exactly K students.
We are given several ants placed at distinct points on a circular track of length (m). Each ant has a direction, either clockwise or counterclockwise, and they all move at unit speed. Whenever two ants meet, they instantly reverse direction.
The city is represented as a line of towers, each with a positive height. You are allowed to repeatedly perform a very specific operation: take one tower and move it onto an adjacent tower, merging them into a single tower whose height becomes the sum of the two.