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 A174774 #17 Aug 12 2013 02:56:00
%S A174774 0,1,3,30,130,780,3696,19768,97560,510660,2603260,13754136,72333768,
%T A174774 390339040,2116922640,11722194240,65521880896,372897624528,
%U A174774 2146502657520,12558129505120,74371827119520,447090649997376
%N A174774 Sum of the numerators for computing the third moment of the probability mass function for probability of k pairs among the involutions on n elements (A000085) assuming equal likelihood.
%H A174774 Wikipedia, <a href="http://en.wikipedia.org/wiki/Probability_mass_function">Probability Mass Function</a>
%F A174774 a(n)=Sum_{k=0..[ n/2 ]} k^3*n!/((n-2*k)!*2^k*k!).
%o A174774 (PARI) a(n) = sum(k=0, n\2 ,k^3*n!/((n-2*k)!*2^k*k!)); \\ _Michel Marcus_, Aug 10 2013
%Y A174774 First moment numerators are given by A162970. The denominator is given by A000085.
%K A174774 nonn
%O A174774 1,3
%A A174774 _Rajan Murthy_, Nov 30 2010
%E A174774 Corrected, and more terms from _Michel Marcus_, Aug 10 2013