OFFSET
0,5
COMMENTS
Number of partitions of n into parts 2, 3, 4, and 9. - Joerg Arndt, Aug 14 2013
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (0,1,1,1,-1,-1,-1,0,2,0,-1,-1,-1,1,1,1,0,-1).
FORMULA
a(n) = floor((2*n^3 + 54*n^2 + 431*n + 2247 + 81*(n+9)*(-1)^n + 192*cos(2*Pi*n/3)*(floor(n/3)+1))/2592). - Tani Akinari, Aug 13 2013
MATHEMATICA
CoefficientList[Series[1/((1-x^2)(1-x^3)(1-x^4)(1-x^9)), {x, 0, 100}], x] (* Jinyuan Wang, Mar 18 2020 *)
LinearRecurrence[{0, 1, 1, 1, -1, -1, -1, 0, 2, 0, -1, -1, -1, 1, 1, 1, 0, -1}, {1, 0, 1, 1, 2, 1, 3, 2, 4, 4, 5, 5, 8, 7, 9, 10, 12, 12}, 70] (* Harvey P. Dale, Aug 18 2024 *)
PROG
(PARI) Vec( 1/((1-x^2)*(1-x^3)*(1-x^4)*(1-x^9)) + O(x^66) ) \\ Joerg Arndt, Aug 14 2013
(PARI) a(n)=round((2*n^3+54*n^2+399*n+899)/2592+(n%3==0)*n/27+(n+9)*(-1)^n/32) \\ Tani Akinari, Jun 03 2014
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved