25524

Appears in sequences

• Number of partitions of n into relatively prime parts. Also aperiodic partitions.at n=38A000837
• Four-column array read by rows: T(n,k) for k=0..3 is the k-th component of the vector obtained by multiplying the n-th power of the 4 X 4 matrix (1,1,1,1; 7,3,1,0; 12,2,0,0; 6,0,0,0) and the vector (1,1,1,1).at n=22A095797
• Product(1 + a(n)*x^n, n=1..infinity) = sum(F(k+1)*x^k, k=1..infinity) = 1/(1-x-x^2), where F(n) = A000045(n) (Fibonacci numbers).at n=27A147542
• Numbers n such that n is the mean value of phi(n) and reversal(n).at n=2A178326
• Number of distinct sums of subsets of the first n squares {1,4,9,...,n^2}.at n=41A208531
• a(n) = a(n-1) + 3*a(n-2) -2*a(n-3) - 2*a(n-4), where a(0) = 1, a(1) = 3, a(2) = 6, a(3) = 10.at n=18A295719
• Numbers k such that at least 7 of k, k+1, ..., k+9 are divisible by their least prime factor squared.at n=2A328817
• a(n) is the number of vertices formed by n-secting the angles of a nonagon (enneagon).at n=38A335782