A025805 Expansion of 1/((1-x^2)*(1-x^4)*(1-x^11)).

1, 0, 1, 0, 2, 0, 2, 0, 3, 0, 3, 1, 4, 1, 4, 2, 5, 2, 5, 3, 6, 3, 7, 4, 8, 4, 9, 5, 10, 5, 11, 6, 12, 7, 13, 8, 14, 9, 15, 10, 16, 11, 17, 12, 19, 13, 20, 14, 22, 15, 23, 16, 25, 17, 26, 19, 28, 20, 29, 22, 31, 23, 32, 25, 34

Offset

0,5

Comments

a(n) is the number of partitions of n into parts 2, 4, and 11. - Hoang Xuan Thanh, Jun 19 2025

Links

Table of n, a(n) for n=0..64.

Index entries for linear recurrences with constant coefficients, signature (0,1,0,1,0,-1,0,0,0,0,1,0,-1,0,-1,0,1).

Formula

a(n) = floor((n^2 + n*(17+11*(-1)^n) + 94*(-1)^n + 131)/176 + (1/11)*[(n mod 11)=8]). - Hoang Xuan Thanh, Jul 07 2025

Mathematica

CoefficientList[Series[1/((1-x^2)(1-x^4)(1-x^11)), {x, 0, 70}], x] (* Harvey P. Dale, Apr 14 2019 *)

Crossrefs

Sequence in context: A274101 A117773 A363824 * A029192 A128619 A008613

Adjacent sequences: A025802 A025803 A025804 * A025806 A025807 A025808

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved