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 A174356 #5 Mar 30 2012 18:52:05 %S A174356 0,2,-12,90,-280,1050,-13860,70070,-48048,4594590,-4618900,106696590, %T A174356 -382444920,966735770,-3123300180,97045398450,-97241449760, %U A174356 3409528332210,-3610088822340,9399601637426,-13492251154200 %N A174356 (-1)^(n+1)*n*A174276(n). %C A174356 The sequence obeys a(n) = A174289(n) - A174290(n), a formula that might be compared to A164869(n) = n*A027642(n) = A164558(n)-A164555(n). %K A174356 frac,sign,easy %O A174356 0,2 %A A174356 _Paul Curtz_, Mar 17 2010