OFFSET
0,4
LINKS
Harry J. Smith, Table of n, a(n) for n = 0..200
Index entries for linear recurrences with constant coefficients, signature (6,-12,10,-3).
FORMULA
G.f.: x^2*(1 + 5*x)/((1 - x)^3*(1 - 3*x)). - Andrew Howroyd, Dec 28 2024
PROG
(PARI) a(n) = { 3^n - (3*n^2 + n + 2)/2 } \\ Harry J. Smith, Jul 29 2009
CROSSREFS
KEYWORD
nonn
AUTHOR
Henry Bottomley, May 24 2001
STATUS
approved