OFFSET
1,4
LINKS
Josep Freixas and Dani Samaniego, On the enumeration of bipartite simple games, Discrete Applied Mathematics, 297 (2021), 129-141.
Index entries for linear recurrences with constant coefficients, signature (0,3,0,-3,0,1).
FORMULA
a(n) = (1/8)*(n^2+14n-24) if n is even.
a(n) = (1/2)*(n-1) if n is odd.
G.f.: (x^5+6*x^4-x^3-10*x^2+3)/((x-1)^3*(x+1)^3).
MATHEMATICA
LinearRecurrence[{0, 3, 0, -3, 0, 1}, {0, 1, 1, 6, 2, 12}, 70] (* Amiram Eldar, Feb 24 2026 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Josep Freixas, Feb 24 2026
STATUS
approved
