A373189 Expansion of Sum_{k>=0} x^(4^k) / (1 - x^(4^k))^3.

1, 3, 6, 11, 15, 21, 28, 39, 45, 55, 66, 84, 91, 105, 120, 147, 153, 171, 190, 225, 231, 253, 276, 321, 325, 351, 378, 434, 435, 465, 496, 567, 561, 595, 630, 711, 703, 741, 780, 875, 861, 903, 946, 1056, 1035, 1081, 1128, 1260, 1225, 1275, 1326, 1469, 1431, 1485, 1540, 1701

Offset: 1

Author

Seiichi Manyama, May 27 2024

Keywords

• nonn

Crossrefs

Cf. A373187, A373188.

Cf. A000217.

Formula

G.f. A(x) satisfies A(x) = x/(1 - x)^3 + A(x^4).

a(4*n+1) = A000217(4*n+1), a(4*n+2) = A000217(4*n+2), a(4*n+3) = A000217(4*n+3) and a(4*n+4) = A000217(4*n+4) + a(n+1) for n >= 0.