A373186 Expansion of Sum_{k>=0} x^(3^k) / (1 - x^(3^k))^3.

1, 3, 7, 10, 15, 24, 28, 36, 52, 55, 66, 88, 91, 105, 135, 136, 153, 195, 190, 210, 259, 253, 276, 336, 325, 351, 430, 406, 435, 520, 496, 528, 627, 595, 630, 754, 703, 741, 871, 820, 861, 1008, 946, 990, 1170, 1081, 1128, 1312, 1225, 1275, 1479, 1378, 1431, 1680, 1540

Offset

1,2

Links

Table of n, a(n) for n=1..55.

Formula

G.f. A(x) satisfies A(x) = x/(1 - x)^3 + A(x^3).

a(3*n+1) = A000217(3*n+1), a(3*n+2) = A000217(3*n+2) and a(3*n+3) = A000217(3*n+3) + a(n+1) for n >= 0.

Crossrefs

Cf. A129527, A373187.

Cf. A327625, A338045.

Cf. A000217.

Sequence in context: A143101 A307612 A330160 * A281642 A353427 A121016

Adjacent sequences: A373183 A373184 A373185 * A373187 A373188 A373189

Keyword

nonn

Author

Seiichi Manyama, May 27 2024

Status

approved