A308509 - OEIS

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A308509

Square array A(n,k), n >= 1, k >= 0, read by antidiagonals, where A(n,k) is Sum_{d|n} d^(k*n/d).

1, 1, 2, 1, 3, 2, 1, 5, 4, 3, 1, 9, 10, 9, 2, 1, 17, 28, 33, 6, 4, 1, 33, 82, 129, 26, 24, 2, 1, 65, 244, 513, 126, 182, 8, 4, 1, 129, 730, 2049, 626, 1458, 50, 41, 3, 1, 257, 2188, 8193, 3126, 11954, 344, 577, 37, 4, 1, 513, 6562, 32769, 15626, 99594, 2402, 8705, 811, 68, 2

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

OFFSET

1,3

LINKS

Seiichi Manyama, Antidiagonals n = 1..140, flattened

FORMULA

L.g.f. of column k: -log(Product_{j>=1} (1 - j^k*x^j)^(1/j)).

A(n,k) = Sum_{d|n} (n/d)^(k*d).

EXAMPLE

Square array begins:

1, 1, 1, 1, 1, 1, 1, ...

2, 3, 5, 9, 17, 33, 65, ...