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^(k+1))).
A(p,k) = 2 for prime p.
EXAMPLE
Square array begins:
1, 1, 1, 1, 1, 1, 1, ...
2, 2, 2, 2, 2, 2, 2, ...
2, 2, 2, 2, 2, 2, 2, ...
3, 4, 6, 10, 18, 34, 66, ...
2, 2, 2, 2, 2, 2, 2, ...
4, 9, 27, 93, 339, 1269, 4827, ...
2, 2, 2, 2, 2, 2, 2, ...
MATHEMATICA
T[n_, k_] := DivisorSum[n, #^(k*(n/# - 1)) &]; Table[T[k, n - k], {n, 1, 12}, {k, 1, n}] // Flatten (* Amiram Eldar, May 09 2021 *)
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Seiichi Manyama, Jun 17 2019
STATUS
approved