OFFSET
0,2
FORMULA
MAPLE
MATHEMATICA
a[n_] := Sum[Hypergeometric2F1[-k, k + 1, -k - 1, n - k], {k, 0, n}];
Table[a[n], {n, 0, 21}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Peter Luschny, Feb 25 2019
STATUS
approved