OFFSET
6,1
LINKS
Index entries for linear recurrences with constant coefficients, signature (3,-3,1,1,-3,3,-1).
FORMULA
a(n)=(n + 6)*(n^2 + 30*n + 71)/12 - 0.375 + 0.125*( - 1)^n - 0.25*cos(n*Pi/2) [From Richard Choulet, Dec 13 2008]
G.f.: x^6*( 35-46*x+18*x^2-x^3-33*x^4-17*x^6+46*x^5 ) / ( (1+x)*(x^2+1)*(x-1)^4 ). - R. J. Mathar, Jun 23 2013
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved