OFFSET
0,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..100
MATHEMATICA
Total/@Table[QBinomial[n, m, -2], {n, 0, 30}, {m, 0, n}] (* Vincenzo Librandi, Oct 23 2012 *)
CROSSREFS
KEYWORD
sign
AUTHOR
STATUS
approved