OFFSET
1,1
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 1..1000
FORMULA
a(n) = binomial(2*n,n) - binomial(2*n,n+2) + 0^(n-1).
PROG
(Haskell)
a230585 1 = 3
a230585 n = a007318 (2*n) n - a007318 (2*n) (n+2)
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Oct 25 2013
STATUS
approved