28938

Appears in sequences

• a(n) = (n+1)*(n^2+n+2)/2; g.f.: (1 + 2*x^2) / (1 - x)^4.at n=38A006000
• Numerators of continued fraction convergents to sqrt(617).at n=7A042184
• Theta series of 14-dimensional lattice M14,3 with minimal norm 6.at n=7A047636
• Expansion of e.g.f.: (1-x)^(-1-x).at n=7A073479
• Numbers n such that the denominator of the 2n-th Bernoulli number is divisible by n but sum_{d|n} sigma(d)/phi(d) is not an integer.at n=16A099008
• Numbers n such that n divides the denominator of 2n-th Bernoulli number.at n=40A106741
• a(n) = 4394*n - 1820.at n=6A156627
• Maximal entry in row n of triangle in A169940.at n=17A169944
• Numbers m such that the GCD of the x's that satisfy sigma(x) = m is 4.at n=31A241649
• Number of n-node unlabeled rooted trees with thickening limbs and root outdegree (branching factor) 3.at n=28A245143
• Numbers k such that card({x|sigma(x)=k}) > 1 and (Sum_{sigma(x)=k} x) < k.at n=35A258931
• The number of monic integer polynomials of degree n all of whose roots are distinct and of modulus at most 1.at n=30A280709
• a(n) = 3*2*1 - 6*5*4 + 9*8*7 - 12*11*10 + 15*14*13 - 18*17*16 + ... - (up to the n-th term).at n=40A319886
• The fifth term of the greedy B_n set of natural numbers.at n=37A369817
• Products of 5 distinct primes that are sandwiched between squarefree semiprime numbers.at n=26A376949