OFFSET
0,2
LINKS
Index entries for linear recurrences with constant coefficients, signature (10,-36,54,-27).
FORMULA
a(n) = ((2*n^2+4*n+3) * 3^(n+1) - 1)/8.
PROG
(PARI) a(n) = ((2*n^2+4*n+3)*3^(n+1)-1)/8;
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Seiichi Manyama, Nov 24 2023
STATUS
approved