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 A055878 #13 Feb 15 2017 19:54:09
%S A055878 1,1,2,1,6,1,43,1,7794,1,387355897233,1,
%T A055878 58111569344245781528237519282283636,1
%N A055878 Least positive sequence with Hankel transform {1,1,1,1,1,...}.
%C A055878 Hankel transform {t(n)} of {a(n)} is given by t(n) = Det[{a(1), a(2), ..., a(n)}, {a(2), a(3), ..., a(n+1)}, ..., {a(n), a(n+1), ..., a(2n-1)}].
%D A055878 M M Mangontarum, O I Cauntongan, A P Macodi-Ringia, The Noncentral Version of the Whitney Numbers: A Comprehensive Study, International Journal of Mathematics and Mathematical Sciences, Volume 2016, Article ID 6206207, 16 pages; http://dx.doi.org/10.1155/2016/6206207. See reference 21.
%H A055878 M. Garcia Armas, B. A. Sethuraman, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL11/Sethuraman/sethuraman2.html">A note on the Hankel Transform of the Central Binomial Coefficients</a>, JIS 11 (2008) 08.5.8
%H A055878 J. W. Layman, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL4/LAYMAN/hankel.html">The Hankel Transform and Some of its Properties</a>, J. Integer Sequences, 4 (2001), #01.1.5.
%Y A055878 Cf. A055877, A055564, A055879.
%K A055878 nonn
%O A055878 1,3
%A A055878 _John W. Layman_, Jul 15 2000
%E A055878 Next term is too large to include.