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 A259330 #5 Aug 16 2015 17:30:40 %S A259330 1,1,1,202,2569966024555163105, %T A259330 76230976900860740792605252290337123070878181006452224000000000000 %N A259330 Ceiling of ((2^n)!)/(2^(n*(n+1))*Product((2^i-1)^2,i=1..n)). %H A259330 C. S. Lorens, <a href="http://dx.doi.org/10.1109/PGEC.1964.263724">Invertible Boolean functions</a>, IEEE Trans. Electron. Computers, EC-13 (1964), 529-541. %H A259330 C. S. Lorens, <a href="/A000722/a000722.pdf">Invertible Boolean functions</a>, IEEE Trans. Electron. Computers, EC-13 (1964), 529-541. [Annotated scan of page 530 only] %K A259330 nonn %O A259330 1,4 %A A259330 _N. J. A. Sloane_, Jun 24 2015