A020071 a(n) = floor( Gamma(n+5/8)/Gamma(5/8) ).

1, 0, 1, 2, 9, 44, 251, 1665, 12700, 109544, 1054363, 11202616, 130230419, 1644159040, 22401666926, 327624378797, 5119130918712, 85105551523594, 1499985345603353, 27937227061862467, 548268081089050917

Offset

0,4

Links

G. C. Greubel, Table of n, a(n) for n = 0..445

Maple

Digits := 64:f := proc(n, x) trunc(GAMMA(n+x)/GAMMA(x)); end;
seq(floor(pochhammer(5/8, n)), n = 0..25); # G. C. Greubel, Nov 17 2019

Mathematica

Floor[Pochhammer[5/8, Range[0, 25]]] (* G. C. Greubel, Nov 17 2019 *)
Table[Floor[(Gamma[n+5/8])/Gamma[5/8]], {n, 0, 20}] (* Harvey P. Dale, Nov 24 2024 *)

Prog

(PARI) vector(26, n, my(x=5/8); gamma(n-1+x)\gamma(x) ) \\ G. C. Greubel, Nov 17 2019
(Magma) [Floor(Gamma(n+5/8)/Gamma(5/8)): n in [0..25]]; // G. C. Greubel, Nov 17 2019
(Sage) [floor(rising_factorial(5/8, n)) for n in (0..25)] # G. C. Greubel, Nov 17 2019

Crossrefs

Cf. A020070, A020072, A020073.

Sequence in context: A119855 A047119 A052881 * A248439 A259778 A260081

Adjacent sequences: A020068 A020069 A020070 * A020072 A020073 A020074

Keyword

nonn

Author

Simon Plouffe

Status

approved