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 A126786 #15 Apr 03 2021 19:04:25 %S A126786 1,2,4,7,6,7,11,11,20,34,17,34,25,19,19,34,27,25,25,26,33,41,36,45,47, %T A126786 49,98,62,40,86,88,82,57,65,67,148,142,67,92,134,61,66,56,68,71,68,63, %U A126786 71,83,97,106,134,77,95,166,186,222,183,113,119,103,103,107,178,134,164 %N A126786 a(n) = n-th positive divisor of ((2n)!/n!^2). %H A126786 David A. Corneth, <a href="/A126786/b126786.txt">Table of n, a(n) for n = 1..10000</a> %e A126786 (2*5)!/5!^2 = 252. The divisors of 252 are 1, 2, 3, 4, 6, 7, 9, 12, 14, 18, 21, 28, 36, 42, 63, 84, 126, 252. The 5th of these is 6. So a(5) = 6. %t A126786 f[n_] := Divisors[(2n)!/n!^2][[n]];Array[f, 66] (* _Ray Chandler_, Feb 26 2007 *) %Y A126786 Cf. A000984. %K A126786 nonn %O A126786 1,2 %A A126786 _Leroy Quet_, Feb 18 2007 %E A126786 Extended by _Ray Chandler_, Feb 26 2007 %E A126786 More terms from _Emeric Deutsch_, Feb 25 2007