A014510 a(n) = floor( Gamma(n+1/2) ).

1, 0, 1, 3, 11, 52, 287, 1871, 14034, 119292, 1133278, 11899423, 136843365, 1710542068, 23092317922, 334838609873, 5189998453040, 85634974475162, 1498612053315336, 27724322986333718, 540624298233507504

Offset

0,4

References

M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, Tenth Printing, 1972, p. 255.

Links

Amiram Eldar, Table of n, a(n) for n = 0..450

M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards, Applied Math. Series 55, Tenth Printing, 1972 [alternative scanned copy].

M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, Tenth Printing, 1972, p. 255.

Formula

a(n)=floor((2n-1)!!/2^n*sqrt(Pi)) where (2n-1)!!=prod(k=1, n, 2*k-1); asymptotically a(n)=n!/sqrt(n)*(1-1/(8n)+1/(128n^2)-5/(1024n^3)+O(1/n^4)) - Benoit Cloitre, Apr 29 2003

Maple

seq(floor(evalf(GAMMA(n+1/2), 100)), n=0..24);

Mathematica

a[n_] := Floor[Gamma[n + 1/2]]; Array[a, 21, 0] (* Amiram Eldar, Sep 20 2019 *)

Crossrefs

Cf. A014511, A014512, A014513, A014514, A014516, A014517, A014518, A014521, A014522.

Sequence in context: A292927 A367046 A179322 * A351067 A058799 A357833

Adjacent sequences: A014507 A014508 A014509 * A014511 A014512 A014513

Keyword

nonn

Author

Simon Plouffe

Status

approved