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 A266911 #8 Jan 08 2016 15:03:01
%S A266911 1,1,2,3,2,2,60,3,10,42,60,30,252,4,8,231,210,2,5460,42,660,1260,840,
%T A266911 210,7956,396,440,228,120,24,720720,2145,510,14490,180,330,17117100,
%U A266911 36036,360,378,26180,3740,3483480,5460,83720,5442360,1755600,2310,2187900,2652,17160,13860,3960,440
%N A266911 GCD of A002443(n) and A002444(n), numerator and denominator in Feinler's formula for the Bernoulli number B_{2n}.
%C A266911 Note that A002443/A002444 = |B_{2n}| = |A000367/A002445|.
%F A266911 a(n) = gcd(A002443(n),A002444(n)).
%Y A266911 Cf. A002443, A002444, A000367, A002445.
%K A266911 nonn
%O A266911 0,3
%A A266911 _M. F. Hasler_, Jan 05 2016
%E A266911 More terms from _N. J. A. Sloane_, Jan 08 2016