This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A014521 #22 Jul 08 2025 05:40:33
%S A014521 2,1,1,3,12,52,288,1871,14034,119292,1133278,11899423,136843365,
%T A014521 1710542068,23092317922,334838609874,5189998453040,85634974475162,
%U A014521 1498612053315336,27724322986333718,540624298233507504
%N A014521 Nearest integer to Gamma(n+1/2).
%D A014521 M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, Tenth Printing, 1972, p. 255.
%H A014521 Amiram Eldar, <a href="/A014521/b014521.txt">Table of n, a(n) for n = 0..450</a>
%H A014521 M. Abramowitz and I. A. Stegun, eds., <a href="http://www.convertit.com/Go/ConvertIt/Reference/AMS55.ASP">Handbook of Mathematical Functions</a>, National Bureau of Standards, Applied Math. Series 55, Tenth Printing, 1972 [alternative scanned copy].
%H A014521 M. Abramowitz and I. A. Stegun, eds., <a href="http://www.convertit.com/Go/ConvertIt/Reference/AMS55.ASP">Handbook of Mathematical Functions</a>, National Bureau of Standards Applied Math. Series 55, Tenth Printing, 1972, p. 255.
%p A014521 [ seq(round(evalf(GAMMA(n+1/2),100)), n=0..24) ];
%t A014521 Table[Round[Gamma[n + 1/2]], {n, 0, 26}]
%o A014521 (PARI) a(n) = round(gamma(n + 1/2)); \\ _Michel Marcus_, Nov 05 2018
%Y A014521 Cf. A014510, A014511, A014512, A014513, A014514, A014516, A014517, A014518, A014522.
%K A014521 nonn
%O A014521 0,1
%A A014521 _N. J. A. Sloane_
%E A014521 a(15) corrected by _Sean A. Irvine_, Nov 04 2018