cp's OEIS Frontend

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.

A140105 Trailing zeros removed from n! in binary.

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%I A140105 #15 Jul 05 2025 14:43:32
%S A140105 1,1,1,11,11,1111,101101,100111011,100111011,101100010011,
%T A140105 11011101011111,100110000100010101,1110010001100111111,
%U A140105 10111001100101000110011,10100010011000011101100101,100110000011101110111011101011,100110000011101110111011101011
%N A140105 Trailing zeros removed from n! in binary.
%H A140105 Robert Israel, <a href="/A140105/b140105.txt">Table of n, a(n) for n = 0..192</a>
%F A140105 a(n) = A007088(A049606(n)). - _Robert Israel_, May 01 2019
%e A140105 a(3)=11 because 3! in binary is 110, which is 11 when the zero is removed.
%p A140105 seq(convert(n!/2^padic:-ordp(n!,2),binary), n=0..30); # _Robert Israel_, May 01 2019
%t A140105 a[n_]:=FromDigits[Drop[IntegerDigits[n!,2],-IntegerExponent[n!,2]]];Array[a,17,0] (* _James C. McMahon_, Jul 04 2025 *)
%Y A140105 Cf. A007088, A049606.
%K A140105 nonn
%O A140105 0,4
%A A140105 _Ben Branman_, Jun 03 2008
%E A140105 a(13)-a(16) from _James C. McMahon_, Jul 04 2025