Questions tagged [sequence]
For challenges involving sequences, typically of numbers following some pattern.
942
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Non-Decreasing Fibonacci Sequence modulo M
Given integers \$a,b,m, k, n\$ and array \$F = (f_1, f_2,...,f_n)\$ defined as:
\begin{cases}
f_1 = \text{a}\\
f_2 = \text{b}\\
f_i = (f_{i-1} + f_{i-2}) \text{ mod m},∀i > 2
\end{cases}
When \$F\$ ...
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Generate a subgroup of a free group
In group theory, the free group with \$n\$ generators can be obtained by taking \$n\$ distinct symbols (let's call them \$a, b, c ...\$ etc), along with their inverses \$ a^{-1},b^{-1},c^{-1} ...\$ . ...
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Smallest Harmonic number greater than N
The sequence of Harmonic numbers are the sums of the reciprocals of the first k natural numbers (not including zero):
\${\displaystyle H_{k}=1+{\frac {1}{2}}+{\frac {1}{3}}+\cdots +{\frac {1}{k}}=\sum ...
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Output the inventory sequence
Goal
Write a program that outputs this list:
...
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Where are zeros? Self-describing sequence
Background
A167519: Lexicographically earliest increasing sequence which lists the positions of the zero digits in the sequence.
...
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Golfing the complexity with subtraction
The Mahler-Popken complexity, \$C(N)\$, of a positive integer, \$N\$, is the smallest number of ones (\$1\$) that can be used to form \$N\$ in a mathematical expression using only the integer* \$1\$ ...
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*Trivial* near-repdigit perfect powers
Task
Output the sequence that precisely consists of the following integers in increasing order:
the 2nd and higher powers of 10 (\$10^i\$ where \$i \ge 2\$),
the squares of powers of 10 times 2 or 3 (...
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Enumerate all matches of a regex
related
For this challenge, we'll be using a simplified dialect of regular expressions, where:
A lowercase letter from a to z ...
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Output a 1-2-3-5-7... sequence
Follow-up of my previous challenge, inspired by @emanresu A's question, and proven possible by @att (Mathematica solution linked)
For the purposes of this challenge, a 1-2-3-5-7... sequence is an ...
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Output a 1-2-3 sequence
For the purposes of this challenge, a 1-2-3 sequence is an infinite sequence of increasing positive integers such that for any positive integer \$n\$, exactly one of \$n, 2n,\$ and \$3n\$ appears in ...
- 2,093
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Odds for second smallest prime factor
Given a prime number \$p\$ output the asymptotic density of the set of positive integers which have \$p\$ as their second-smallest distinct prime factor
Input/Output
Input: one of the following ...
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Rank poker High Card hands [closed]
In the poker game there are 1277 unique 'High Card' ranks. It's 1287 (13 over 5) if we include all straights.
The challenge is to write a function which returns an integer value corresponding to the ...
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How quickly can you type this unary string?
If I want to type the string aaa, the least keystrokes I can type it in is 3: a a a. But if I want to type the string ...
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Pretty Palintiples
Imagine you have a positive integer number \$n\$. Let \$m\$ be the number obtained by reversing \$n\$'s digits. If \$m\$ is a whole multiple of \$n\$, then \$n\$ is said to be a reverse divisible ...
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Enumerate the Phat-fingered-lights-out numbers
Even though the concept of phat-fingered-lights-out number should be pretty self-explanatory here is a definition:
Given a nonnegative integer in binary representation a phat-fingered double-bit-flip ...
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