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 A002701 M4424 N1870 #28 Feb 28 2019 11:45:06 %S A002701 1,1,7,41,479,59,266681,63397,514639,178939,10410343,18500393, %T A002701 40799043101,1411432849,6620481151,48409924397,238357395880861, %U A002701 339716530787,86364397717734821,421950627598601,222226462279,15392144025383 %N A002701 Coefficients for numerical differentiation. %D A002701 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence). %D A002701 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %H A002701 H. E. Salzer, <a href="https://doi.org/10.1002/sapm1943221115">Coefficients for numerical differentiation with central differences</a>, J. Math. Phys., 22 (1943), 115-135. %H A002701 H. E. Salzer, <a href="/A002457/a002457_2.pdf">Coefficients for numerical differentiation with central differences</a>, J. Math. Phys., 22 (1943), 115-135. [Annotated scanned copy] %H A002701 T. R. Van Oppolzer, <a href="http://www.archive.org/stream/lehrbuchzurbahnb02oppo#page/21/mode/1up">Lehrbuch zur Bahnbestimmung der Kometen und Planeten</a>, Vol. 2, Engelmann, Leipzig, 1880, p. 21 (see numerators of numbers named N(3,2k+1) and N(4,2k)). %F A002701 a(n) = numer(6 * A002455(n) / 2^(2*n) * (2*n + 3)!). - _Sean A. Irvine_, Jun 10 2014 %Y A002701 Cf. A002455 (central factorial numbers), A002702 (denominators). %K A002701 nonn,frac %O A002701 2,3 %A A002701 _N. J. A. Sloane_ %E A002701 More terms from _Sean A. Irvine_, Jun 10 2014