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A233568
a(n) is number in A114994 which c-equivalent to c-factorial of n (A047778).
0
1, 5, 23, 151, 1199, 9567, 76543, 1125119, 17978879, 287659519, 4602550271, 73629609983, 1178073743359, 18849179828223, 301586877251583, 9308786131992575, 297840749160955903, 9530903606625042431, 304988913945966280703, 9759645240406772285439
OFFSET
1,2
COMMENTS
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.
EXAMPLE
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.
MATHEMATICA
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 *)
CROSSREFS
Sequence in context: A128884 A356436 A007836 * A157306 A306185 A336183
KEYWORD
nonn
AUTHOR
Vladimir Shevelev, Dec 13 2013
STATUS
approved