OFFSET
0,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..300
FORMULA
E.g.f.: 9*x/(1-x).
a(n) = n*a(n-1) = 9*A000142(n) for n>0.
MATHEMATICA
Join[{0}, 9 Range[25]!]
PROG
(Magma) [n eq 0 select 0 else 9*Factorial(n): n in [0..25]];
(PARI) a(n) = (n > 0)*9*n! \\ Felix Fröhlich, Feb 15 2018
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Feb 14 2018
STATUS
approved