OFFSET
0,4
COMMENTS
Row sums of A122440.
FORMULA
a(n) = -hypergeometric([1-n, n], [-n], -2) if n>0. - Peter Luschny, Nov 30 2014
PROG
(Sage)
def a(n):
if n==0: return 1
return -hypergeometric([1-n, n], [-n], -2).simplify()
[a(n) for n in range(21)] # Peter Luschny, Nov 30 2014
CROSSREFS
KEYWORD
easy,sign
AUTHOR
Paul Barry, Sep 05 2006
STATUS
approved