OFFSET
1,1
LINKS
Index entries for linear recurrences with constant coefficients, signature (15,-90,270,-405,243).
FORMULA
O.g.f.: z*3^3*(2-3*z)/(1-3*z)^5.
a(n) = A287768(n+7,9).
MATHEMATICA
Table[1/4! 3^(n+2) (n+7)(n+2)(n+1)n, {n, 30}] (* or *) LinearRecurrence[{15, -90, 270, -405, 243}, {54, 729, 6075, 40095, 229635}, 30] (* Harvey P. Dale, May 15 2022 *)
PROG
(PARI) a(n)=3^n*3*n*(n+1)*(n+2)*(n+7)/8 \\ Charles R Greathouse IV, Jun 19 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Gregory Gerard Wojnar, Jun 17 2017
STATUS
approved