OFFSET
1,2
EXAMPLE
The first few fractions b(n) are 1, 2, 3/2, 8/3, 15/8, 16/5, 35/16, 128/35, 315/128, 256/63, 693/256, 1024/231, 3003/1024, 2048/429, ...
MATHEMATICA
a[n_] := Floor[n!!/(n - 1)!!]; Array[a, 90] (* Robert G. Wilson v, Dec 06 2020 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Nov 29 2020, following a suggestion from Anchar Koops, Nov 24 2020
STATUS
approved