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Square array A(n,k), n >= 0, k >= 1, read by antidiagonals, where column k is the expansion of Product_{j>=1} (1 + x^j)/(1 + x^(k*j)).
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%I #11 Mar 29 2019 15:51:20

%S 1,1,0,1,1,0,1,1,0,0,1,1,1,1,0,1,1,1,1,1,0,1,1,1,2,1,1,0,1,1,1,2,1,2,

%T 1,0,1,1,1,2,2,2,2,1,0,1,1,1,2,2,2,3,3,2,0,1,1,1,2,2,3,3,3,3,2,0,1,1,

%U 1,2,2,3,3,4,4,3,2,0,1,1,1,2,2,3,4,4,4,5,4,2,0,1,1,1,2,2,3,4,4,5,6,6,5,3,0

%N Square array A(n,k), n >= 0, k >= 1, read by antidiagonals, where column k is the expansion of Product_{j>=1} (1 + x^j)/(1 + x^(k*j)).

%C A(n,k) is the number of partitions of n into distinct parts where no part is a multiple of k.

%H Seiichi Manyama, <a href="/A290307/b290307.txt">Antidiagonals n = 0..139, flattened</a>

%H <a href="/index/Par#part">Index entries for sequences related to partitions</a>

%F G.f. of column k: Product_{j>=1} (1 + x^j)/(1 + x^(k*j)).

%F For asymptotics of column k see comment from _Vaclav Kotesovec_ in A261772.

%e Square array begins:

%e 1, 1, 1, 1, 1, 1, ...

%e 0, 1, 1, 1, 1, 1, ...

%e 0, 0, 1, 1, 1, 1, ...

%e 0, 1, 1, 2, 2, 2, ...

%e 0, 1, 1, 1, 2, 2, ...

%e 0, 1, 2, 2, 2, 3, ...

%t Table[Function[k, SeriesCoefficient[Product[(1 + x^i)/(1 + x^(i k)), {i, Infinity}], {x, 0, n}]][j - n + 1], {j, 0, 13}, {n, 0, j}] // Flatten

%t Table[Function[k, SeriesCoefficient[QPochhammer[-1, x]/QPochhammer[-1, x^k], {x, 0, n}]][j - n + 1], {j, 0, 13}, {n, 0, j}] // Flatten

%Y Columns k=1-10 give: A000007, A000700, A003105, A070048, A096938, A261770, A097793, A261771, A112193, A261772.

%Y Cf. A286653.

%K nonn,tabl

%O 0,25

%A _Ilya Gutkovskiy_, Jul 26 2017