Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #5 Aug 16 2015 17:29:55
%S 2,1,2,51480,2631645209144487019355,
%T 312242081385925594286511113381220856098317029402428309504000000000000
%N Ceiling of ((2^n)!)/(2^(n*(n-1))*Product((2^i-1)^2,i=1..n))
%H 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 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 nonn
%O 1,1
%A _N. J. A. Sloane_, Jun 24 2015