218295

Appears in sequences

• Number of graphs on n nodes with 3 cliques.at n=34A005289
• Odd values arising in A066820.at n=6A066852
• Least number m such that the Sigma-Harmonic sequence Sum_{k=1..m} 1/sigma(k) >= n.at n=8A074468
• Triangle read by rows: coefficients of expansion in powers of x of the polynomials defined by p(n, x) = (2*n - 1)*p(n - 1, x) + (n - 1)^2*x^2*p(n - 2, x).at n=30A123244
• Partition number array, called M32(-3), related to A000369(n,m) = |S2(-3;n,m)| (generalized Stirling triangle).at n=31A143173
• Numbers with exactly 4 distinct odd prime divisors {3,5,7,11}.at n=27A147577
• a(n) = 531441*n - 313146.at n=0A157377
• Triangle T(n,k), 0 <= k <= n, given by (0, 1, 0, 2, 0, 3, 0, 4, 0, 5, ...) DELTA (1, 2, 3, 4, 5, 6, 7, 8, 9, ...) where DELTA is the operator defined in A084938.at n=34A211608
• Triangle read by rows: coefficients of polynomials P_n(x) arising from RNA combinatorics.at n=20A270791
• a(1) = 1. For n > 1, a(n) = a(n-1)/2 if a(n-1) is even, a(n) = a(n-1)*n otherwise.at n=26A290650
• a(n) is the least number k that has exactly n divisors <= sqrt(k) of the form 4*j+1.at n=16A379693
• Numbers k with a record number of proper divisors, where all of them have binary weights that are different from the binary weight of k.at n=16A383365