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 A066449 #29 Jul 15 2014 04:59:48
%S A066449 1,2,3,6,5,15,7,70,84,210,11,495,13,3003,6435,12870,17,18564,19,
%T A066449 125970,293930,646646,23,735471,53130,9657700,4686825,30421755,29,
%U A066449 5852925,31,601080390,573166440,2203961430,417225900,1251677700,37,33578000610
%N A066449 Binomial(n, phi(n)), where phi(n) is the Euler totient function.
%C A066449 This is also binomial(n, cototient(n)). - _Franklin T. Adams-Watters_, Jul 13 2014
%H A066449 Harry J. Smith, <a href="/A066449/b066449.txt">Table of n, a(n) for n=1..300</a>
%e A066449 a(6) = binomial(6, phi(6)) = binomial(6, 2) = 6!/(2!*4!) = 15.
%p A066449 seq(binomial(n, numtheory:-phi(n)), n=1..100); # _Robert Israel_, Jul 13 2014
%t A066449 Map[Binomial[#, EulerPhi[#]] &, Range[80]] (* _Carl Najafi_, Aug 30 2011 *)
%o A066449 (PARI) { for (n=1, 300, a=binomial(n, eulerphi(n)); write("b066449.txt", n, " ", a) ) } \\ _Harry J. Smith_, Feb 15 2010
%Y A066449 Cf. A000010, A051953, A066090, A064366.
%K A066449 easy,nonn
%O A066449 1,2
%A A066449 _Joseph L. Pe_, Dec 28 2001
%E A066449 a(16) - a(38) from _Harry J. Smith_, Feb 15 2010