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%I #19 Jan 06 2018 18:46:31
%S 1,1,-1,1,0,-1,1,-1,0,0,1,-1,1,0,0,1,-1,-1,-2,0,1,1,-1,-1,3,3,0,0,1,
%T -1,-1,0,-3,-4,0,1,1,-1,-1,0,4,-2,5,0,0,1,-1,-1,0,0,-3,9,-7,0,0,1,-1,
%U -1,0,0,6,-4,-8,10,0,0,1,-1,-1,0,0,1,-5,1,-6,-13,0,0,1
%N Square array A(n,k), n>=0, k>=0, read by antidiagonals, where column k is the expansion of Product_{j>=1} (1 - x^j)/(1 - x^(k*j))^k.
%H Seiichi Manyama, <a href="/A286950/b286950.txt">Antidiagonals n = 0..139, flattened</a>
%F G.f. of column k: Product_{j>=1} (1 - x^j)/(1 - x^(k*j))^k.
%e Square array begins:
%e 1, 1, 1, 1, 1, ...
%e -1, 0, -1, -1, -1, ...
%e -1, 0, 1, -1, -1, ...
%e 0, 0, -2, 3, 0, ...
%e 0, 0, 3, -3, 4, ...
%Y Columns k=0-4 give: A010815, A000007, A106507, A286952, A286953.
%Y Diagonal gives A286956.
%Y Cf. A175595.
%K sign,tabl
%O 0,19
%A _Seiichi Manyama_, May 17 2017