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%I #10 Jul 08 2024 08:53:44
%S 1,3,3,2,2,2,4,5,3,2,2,4,5,3,2,4,7,4,3,3,2,7,6,5,2,2,5,4,8,6,5,3,3,6,
%T 6,4,5,7,6,5,3,6,5,8,4,3,7,5,5,4,8,11,6,4,3,5,12,7,6,1,8,7,3,6,4,6,7,
%U 12,6,5,4,9,11,11,4,1,5,8,11,7,6,9,8,4,6,7,10,3,8,4,4,10,8,9,9,11,7,7,8,10,4
%N Number of ways to write n as an ordered sum of a triangular number, a pentagonal number and a hexagonal number.
%H Seiichi Manyama, <a href="/A374409/b374409.txt">Table of n, a(n) for n = 0..10000</a>
%F G.f.: (Sum_{k>=0} x^(k*(k+1)/2)) * (Sum_{k>=0} x^(k*(3*k-1)/2)) * (Sum_{k>=0} x^(k*(2*k-1))).
%Y Cf. A000217, A000326, A000384, A240088.
%K nonn
%O 0,2
%A _Seiichi Manyama_, Jul 08 2024