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 A024378 #12 Apr 27 2017 22:47:07 %S A024378 5,59,254,730,1675,3325,5964,9924,15585,23375,33770,47294,64519,86065, %T A024378 112600,144840,183549,229539,283670,346850,420035,504229,600484, %U A024378 709900,833625,972855,1128834,1302854,1496255,1710425,1946800,2206864,2492149 %N A024378 a(n) = 2nd elementary symmetric function of the first n+1 positive integers congruent to 1 mod 4. %H A024378 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (5,-10,10,-5,1). %F A024378 a(n) = n*(n+1)*(12*n^2+8*n-5)/6. %F A024378 G.f.: -x*(5+34*x+9*x^2) / (x-1)^5. - _R. J. Mathar_, Oct 08 2011 %p A024378 A024378:=n->n*(n+1)*(12*n^2+8*n-5)/6: seq(A024378(n), n=1..50); # _Wesley Ivan Hurt_, Apr 27 2017 %K A024378 nonn,easy %O A024378 1,1 %A A024378 _Clark Kimberling_