OFFSET
0,3
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..200
FORMULA
a(n) = ((2n)!/2^n + n!) / (2n).
CROSSREFS
KEYWORD
nonn
AUTHOR
Max Alekseyev, Feb 09, 2008
EXTENSIONS
a(0)=1 prepended by Alois P. Heinz, Jul 28 2015
STATUS
approved