25823

Appears in sequences

• Smallest composite which when sum of prime factors is repeatedly subtracted reaches a prime after n iterations.at n=33A053093
• Number of distinct products i*j*k*l for 1 <= i <= j <= k <= l <= n.at n=40A100437
• Indices of prime numbers in A014259.at n=12A101761
• Numbers k such that phi(phi(k)) = sigma(rad(k)).at n=33A173748
• Numbers n for which phi(n)=sigma(n'), where phi is the Euler totient function, sigma is the sum of divisors and n' the arithmetic derivative of n.at n=11A189057
• Nonnegative values x of solutions (x, y) to the Diophantine equation x^2+(x+217)^2 = y^2.at n=27A198294
• a(n) = Sum_{i=0..n} digsum_8(i)^3, where digsum_8(i) = A053829(i).at n=56A231682
• Number of strict partitions of 2n having an ordering of the parts in which no two neighboring parts have the same parity.at n=38A239882
• Number of partitions p of n such that (maximal multiplicity of the parts of p) <= (maximal part of p).at n=39A240311
• Number of integer partitions of the n-th even number or the n-th odd number using predecessors of prime numbers.at n=36A280962
• G.f. A(x) satisfies: [x^n] A(x)^(n+1) = [x^n] (1 + x*A(x)^n)^(n+1) for n>=0.at n=6A302702
• Number of integer partitions of n whose Heinz number (product of primes of parts) is divisible by all parts.at n=47A330952
• Number of distinct characteristic polynomials for 2 X 2 matrices with entries from {0, 1, ..., n}.at n=25A366448