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Expansion of Product_{k=1..9} (1+x^(2*k-1))/(1-x^(2*k)).
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%I #12 Jul 12 2018 03:09:34

%S 1,1,1,2,3,4,5,7,10,13,16,21,28,35,43,55,70,86,105,129,159,193,231,

%T 279,338,403,477,568,675,795,932,1094,1284,1497,1736,2016,2340,2700,

%U 3105,3573,4106,4699,5363,6118,6972,7921,8974,10163,11500,12974,14606,16435,18471

%N Expansion of Product_{k=1..9} (1+x^(2*k-1))/(1-x^(2*k)).

%H Seiichi Manyama, <a href="/A316721/b316721.txt">Table of n, a(n) for n = 0..10000</a>

%t nmax=50; CoefficientList[Series[Product[(1 + x^(2 k - 1)) / (1 - x^(2 k)), {k, 1, 9}], {x, 0, nmax}], x] (* _Vincenzo Librandi_, Jul 12 2018 *)

%o (PARI) N=99; x='x+O('x^N); Vec(prod(k=1, 9, (1+x^(2*k-1))/(1-x^(2*k))))

%Y Product_{k=1..b} (1+x^(2*k-1))/(1-x^(2*k)): A000012 (b=1), A004525(n+1) (b=2), A000933(n+5) (b=3), A089597 (b=4), A014670 (b=5), A316718 (b=6), A316719 (b=7), A316720 (b=8), this sequence (b=9), A316722 (b=10).

%Y Cf. A316675.

%K nonn

%O 0,4

%A _Seiichi Manyama_, Jul 11 2018