OFFSET
0,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..200
FORMULA
a(n) = 6 * A034001(n) for n >= 1.
a(n) = 2*3^n*n! - 0^n.
Sum_{n>=0} 1/a(n) = (exp(1/3)+1)/2. - Amiram Eldar, Feb 02 2023
MATHEMATICA
Join[{1}, Table[2*3^n n!, {n, 20}]] (* Harvey P. Dale, Aug 08 2014 *)
PROG
(Magma) [2*3^n*Factorial(n)-0^n: n in [0..20]]; // Vincenzo Librandi, Aug 08 2014
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Sep 14 2004
STATUS
approved