

A329465


Expansion of Sum_{k>=1} (1 + Product_{j>=1} 1 / (1  x^(k*j*(j + 1)/2))).


1



1, 2, 3, 4, 3, 8, 5, 8, 9, 11, 8, 20, 12, 17, 20, 25, 18, 36, 25, 38, 39, 44, 37, 68, 51, 63, 69, 85, 69, 113, 90, 117, 117, 136, 128, 189, 154, 185, 195, 239, 206, 288, 253, 308, 321, 358, 333, 457, 406, 476, 485, 566, 521, 671, 629, 734, 737, 833, 794, 1019
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OFFSET

1,2


COMMENTS

Inverse Moebius transform of A007294.


LINKS

Table of n, a(n) for n=1..60.


FORMULA

G.f.: Sum_{k>=1} A007294(k) * x^k / (1  x^k).
a(n) = Sum_{dn} A007294(d).


MATHEMATICA

nmax = 60; CoefficientList[Series[Sum[1 + Product[1/(1  x^(k j (j + 1)/2)), {j, 1, nmax}], {k, 1, nmax}], {x, 0, nmax}], x] // Rest


CROSSREFS

Cf. A007294, A047966, A047968, A329439, A329466.
Sequence in context: A324150 A198461 A228576 * A324195 A211507 A295368
Adjacent sequences: A329462 A329463 A329464 * A329466 A329467 A329468


KEYWORD

nonn


AUTHOR

Ilya Gutkovskiy, Nov 13 2019


STATUS

approved



