A374410 Number of ways to write n as an ordered sum of a triangular number, a heptagonal number and an octagonal number.
1, 3, 3, 2, 2, 1, 1, 3, 4, 3, 3, 4, 2, 1, 2, 3, 3, 2, 4, 3, 1, 4, 6, 4, 3, 3, 1, 2, 5, 7, 3, 2, 2, 1, 3, 3, 7, 5, 3, 2, 4, 4, 4, 6, 4, 5, 4, 5, 2, 4, 4, 2, 2, 3, 4, 6, 8, 5, 4, 2, 2, 4, 6, 6, 5, 3, 6, 5, 5, 3, 5, 4, 2, 6, 4, 6, 6, 5, 4, 5, 4, 4, 4, 6, 7, 4, 7, 6, 2, 4, 2, 6, 7, 5, 4, 4, 5, 6, 4, 7, 8, 4, 7, 5
Offset: 0
Keywords
Links
- Seiichi Manyama, Table of n, a(n) for n = 0..10000
Formula
G.f.: (Sum_{k>=0} x^(k*(k+1)/2)) * (Sum_{k>=0} x^(k*(5*k-3)/2)) * (Sum_{k>=0} x^(k*(3*k-2))).