cp's OEIS Frontend

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.

A003704 Expansion of log(1+sinh(x)).

This page as a plain text file.
%I A003704 M2867 #28 Feb 16 2015 09:40:36
%S A003704 0,1,-1,3,-10,45,-256,1743,-13840,125625,-1282816,14554683,-181649920,
%T A003704 2473184805,-36478744576,579439207623,-9861412096000,179018972217585,
%U A003704 -3452931391553536,70518070842040563,-1520176422094766080
%N A003704 Expansion of log(1+sinh(x)).
%D A003704 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H A003704 Vincenzo Librandi, <a href="/A003704/b003704.txt">Table of n, a(n) for n = 0..200</a>
%F A003704 a(n) = sum(k=1..n, sum(i=0..k, (-1)^(n+i-1)*(k-2*i)^n * binomial(k,i)) /(k*2^k)). [_Vladimir Kruchinin_, Apr 20 2011]
%F A003704 a(n) ~ (-1)^(n+1) * (n-1)! / (log(1+sqrt(2)))^n. - _Vaclav Kotesovec_, Feb 16 2015
%t A003704 With[{nn = 201}, CoefficientList[Series[Log[1 + Sinh[x]], {x, 0, nn}], x] Range[0, nn]!] (* _Vincenzo Librandi_, Apr 11 2014 *)
%o A003704 (Maxima)
%o A003704 a(n):=sum(sum((-1)^(n+i-1)*(k-2*i)^n*binomial(k,i),i,0,k)/(k*2^k),k,1,n); /* _Vladimir Kruchinin_, Apr 20 2011 */
%Y A003704 Cf. A009344, A024293, A080795.
%K A003704 sign
%O A003704 0,4
%A A003704 _R. H. Hardin_, _Simon Plouffe_
%E A003704 Mathematica code replaced by _Vincenzo Librandi_, Apr 11 2014