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A103676 Numbers m such that in binary representation m! contains 5!. 5

%I #16 Nov 21 2013 12:48:38

%S 5,10,12,22,23,25,27,29,33,34,35,37,38,39,40,41,42,43,44,45,47,48,49,

%T 50,51,52,54,55,56,57,59,60,61,62,63,64,66,67,68,69,70,71,72,73,74,75,

%U 76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99

%N Numbers m such that in binary representation m! contains 5!.

%C Complement of A103677: A103673(a(n))=1, A103673(A103677(n))=0.

%H <a href="/index/Fa#factorial">Index entries for sequences related to factorial numbers</a>

%H <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>

%t Select[Range[100],MemberQ[Partition[IntegerDigits[#!,2],7,1],{1,1,1,1,0,0,0}]&] (* _Harvey P. Dale_, Apr 09 2012 *)

%o (PARI) is(n)=n=n!; while(n>119, my(e=valuation(n, 2), e1=valuation((n>>=e)+1, 2)); n>>=e1; if(e>2 && e1>3, return(1))); 2 \\ _Charles R Greathouse IV_, Apr 07 2013

%Y Cf. A102730, A036603, A007088, A000142, A103678, A103680.

%K nonn,base

%O 1,1

%A _Reinhard Zumkeller_, Feb 12 2005

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Last modified May 15 04:08 EDT 2024. Contains 372536 sequences. (Running on oeis4.)