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G.f.: Product_{m>0} (1 + x^m + 2*x^(2*m) + 3*x^(3*m)).
2

%I #13 Oct 07 2017 03:21:32

%S 1,1,3,5,6,10,18,25,34,53,66,94,136,179,236,325,416,550,714,913,1181,

%T 1530,1917,2446,3091,3862,4828,6051,7457,9233,11465,14028,17181,21099,

%U 25651,31251,37948,45853,55380,66833,80236,96271,115496,137822,164470,196094,232837

%N G.f.: Product_{m>0} (1 + x^m + 2*x^(2*m) + 3*x^(3*m)).

%H Seiichi Manyama, <a href="/A290269/b290269.txt">Table of n, a(n) for n = 0..500</a>

%o (PARI) m = 30; Vec(prod(k=1, m, 1 + x^k + 2*x^(2*k) + 3*x^(3*k)) + O(x^m)) \\ _Michel Marcus_, Oct 07 2017

%Y Column k=3 of A290216.

%K nonn

%O 0,3

%A _Seiichi Manyama_, Oct 06 2017