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A286656
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)).
1
1, 1, 0, 1, -1, 0, 1, -1, 0, 0, 1, -1, -1, -1, 0, 1, -1, -1, 1, 1, 0, 1, -1, -1, 0, -1, -1, 0, 1, -1, -1, 0, 1, 0, 1, 0, 1, -1, -1, 0, 0, 0, 2, -1, 0, 1, -1, -1, 0, 0, 2, -1, -1, 2, 0, 1, -1, -1, 0, 0, 1, -1, 1, -1, -2, 0, 1, -1, -1, 0, 0, 1, 1, 0, 2, 3, 2, 0, 1
OFFSET
0,43
FORMULA
G.f. of column k: Product_{j>=1} (1 - x^j)/(1 - x^(k*j)).
EXAMPLE
Square array begins:
1, 1, 1, 1, 1, ...
0, -1, -1, -1, -1, ...
0, 0, -1, -1, -1, ...
0, -1, 1, 0, 0, ...
0, 1, -1, 1, 0, ...
CROSSREFS
Columns k=1-5 give: A000007, A081362, A137569, A082303, A145466.
Main diagonal gives A010815.
Cf. A286653.
Sequence in context: A280126 A178536 A360001 * A048484 A298601 A016366
KEYWORD
sign,tabl
AUTHOR
Seiichi Manyama, May 14 2017
STATUS
approved