A025804 Expansion of 1/((1-x^2)*(1-x^4)*(1-x^9)).

1, 0, 1, 0, 2, 0, 2, 0, 3, 1, 3, 1, 4, 2, 4, 2, 5, 3, 6, 3, 7, 4, 8, 4, 9, 5, 10, 6, 11, 7, 12, 8, 13, 9, 14, 10, 16, 11, 17, 12, 19, 13, 20, 14, 22, 16, 23, 17, 25, 19, 26, 20, 28, 22, 30, 23, 32, 25, 34, 26, 36, 28, 38, 30, 40

Offset

0,5

Comments

a(n) is the number of partitions of n into parts 2, 4, and 9. - Hoang Xuan Thanh, Jun 18 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,-1,0,0,1,0,-1,0,-1,0,1).

Formula

a(n) = floor((n^2 + n*(15+9*(-1)^n) + 116 + 64*(-1)^n)/144). - Hoang Xuan Thanh, Jun 18 2025

Prog

(PARI) Vec(1/((1-x^2)*(1-x^4)*(1-x^9))+O(x^99)) \\ Charles R Greathouse IV, Sep 27 2012

Crossrefs

Sequence in context: A164092 A302643 A319973 * A042961 A029190 A166865

Adjacent sequences: A025801 A025802 A025803 * A025805 A025806 A025807

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved