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 A081046 #17 Feb 13 2016 03:56:35 %S A081046 1,-2,5,-17,74,-394,2484,-18108,149904,-1389456,14257440,-160460640, %T A081046 1965444480,-26029779840,370643938560,-5646837369600,91657072281600, %U A081046 -1579093018675200,28779361764249600,-553210247226470400 %N A081046 Difference of the first two Stirling numbers of the first kind. %F A081046 a(n) = s(n, 1)-s(n, 2), s(n, m) = signed Stirling number of the first kind. %F A081046 E.g.f.: (1+x)^-1 * (1-log(1+x)). %F A081046 Conjecture: a(n) +(2*n-1)*a(n-1) +(n-1)^2*a(n-2)=0. - _R. J. Mathar_, Oct 27 2014 %t A081046 Table[StirlingS1[n+1, 1] - StirlingS1[n+1, 2], {n, 0, 20}] (* or *) Table[(-1)^n n! (1+HarmonicNumber[n]), {n, 0, 20}] (* _Jean-François Alcover_, Feb 11 2016 *) %o A081046 (PARI) a(n) = stirling(n+1, 1, 1) - stirling(n+1, 2, 1); \\ _Michel Marcus_, Feb 11 2016 %Y A081046 Cf. A000254, A008275. Same as A000774 apart from signs. %K A081046 easy,sign %O A081046 0,2 %A A081046 _Paul Barry_, Mar 05 2003