OFFSET
1,7
LINKS
Eric Weisstein's World of Mathematics, Graph Cycle
Index entries for linear recurrences with constant coefficients, signature (3, -3, 1).
FORMULA
For n >= 7, a(n) = 6*(292 - 90*n + 7*n^2).
For n >= 10, a(n) = 3*a(n-1)-3*a(n-2)+a(n-3).
G.f.: -6*x^7*(5 + 5*x + 4*x^2)/(-1 + x)^3.
MATHEMATICA
Table[If[n < 7, 0, 6 (292 - 90 n + 7 n^2)], {n, 20}]
Join[{0, 0, 0, 0, 0, 0}, LinearRecurrence[{3, -3, 1}, {30, 120, 294}, 14]]
CoefficientList[Series[-((6 x^6 (5 + 5 x + 4 x^2))/(-1 + x)^3), {x, 0, 20}], x]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Eric W. Weisstein, Jul 29 2017
STATUS
approved