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 A233568 #9 Dec 14 2013 20:01:34 %S A233568 1,5,23,151,1199,9567,76543,1125119,17978879,287659519,4602550271, %T A233568 73629609983,1178073743359,18849179828223,301586877251583, %U A233568 9308786131992575,297840749160955903,9530903606625042431,304988913945966280703,9759645240406772285439 %N A233568 a(n) is number in A114994 which c-equivalent to c-factorial of n (A047778). %C A233568 Two numbers n_1 and n_2 are called c-equivalent (n_1~n_2) if in binary they have the same parts of the form 10...0 with k>=0 zeros up to a permutation of them. For example, 6~5, 14~13~11, 12~9. %e A233568 A047778(4)=220 which has parts (1)(10)(1)(1)(100)~(100)(10)(1)(1)(1) which is 151 in decimal. So, a(4)=151. %t A233568 bitPatt[n_]:=bitPatt[n]=Split[IntegerDigits[n,2],#1>#2||#2==0&];Map[FromDigits[Flatten[Reverse[Sort[bitPatt[FromDigits[Flatten[Map[IntegerDigits[#,2]&,Range[#]]],2]]]]],2]&,Range[20]] (* _Peter J. C. Moses_, Dec 14 2013 *) %K A233568 nonn %O A233568 1,2 %A A233568 _Vladimir Shevelev_, Dec 13 2013