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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 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,43

LINKS

Table of n, a(n) for n=0..78.

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: A321763 A280126 A178536 * A048484 A298601 A016366

Adjacent sequences:  A286653 A286654 A286655 * A286657 A286658 A286659

KEYWORD

sign,tabl

AUTHOR

Seiichi Manyama, May 14 2017

STATUS

approved

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Last modified September 18 02:54 EDT 2021. Contains 347504 sequences. (Running on oeis4.)