OFFSET
0,5
COMMENTS
a(n) is the number of partitions of n into parts 2, 4, 7, and 10. - Hoang Xuan Thanh, Oct 11 2025
LINKS
Index entries for linear recurrences with constant coefficients, signature (0,1,0,1,0,-1,1,0,-1,1,-1,-1,1,-1,0,1,-1,0,1,0,1,0,-1).
FORMULA
G.f.: 1/((1-x^2)*(1-x^4)*(1-x^7)*(1-x^10)).
a(n) = a(n-2) + a(n-4) - a(n-6) + a(n-7) - a(n-9) + a(n-10) - a(n-11) - a(n-12) + a(n-13) - a(n-14) + a(n-16) - a(n-17) + a(n-19) + a(n-21) - a(n-23). - Wesley Ivan Hurt, Jun 26 2025
a(n) = floor((n^3+45*n^2+596*n+2112)/3360 - (n^2+23*n+96)*(n mod 2)/160 + ((5*n^3+n^2+5*n+4) mod 7)/7). - Hoang Xuan Thanh, Oct 11 2025
MATHEMATICA
CoefficientList[Series[1/((1-x^2)(1-x^4)(1-x^7)(1-x^10)), {x, 0, 60}], x] (* or *) LinearRecurrence[{0, 1, 0, 1, 0, -1, 1, 0, -1, 1, -1, -1, 1, -1, 0, 1, -1, 0, 1, 0, 1, 0, -1}, {1, 0, 1, 0, 2, 0, 2, 1, 3, 1, 4, 2, 5, 2, 7, 3, 8, 4, 10, 5, 12, 7, 14}, 70] (* Harvey P. Dale, Apr 11 2018 *)
PROG
(PARI) Vec(1/((1-x^2)*(1-x^4)*(1-x^7)*(1-x^10)) + O(x^80)) \\ Jinyuan Wang, Feb 28 2020
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved
