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%I #15 Nov 16 2017 15:50:17
%S 0,1,2,3,4,6,7,8,9,11,13,14,15,16,17,18,19,20,21,24,26,28,30,31,32,36,
%T 46,53,58,65
%N Numbers m such that in binary representation m! doesn't contain 5!.
%C Conjecture: there are no further terms;
%C complement of A103676: A103673(a(n))=0, A103673(A103676(n))=1.
%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>
%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(0))); 1 \\ _Charles R Greathouse IV_, Apr 07 2013
%Y Cf. A102730, A036603, A007088, A000142, A103679, A103681.
%K nonn,base
%O 1,3
%A _Reinhard Zumkeller_, Feb 12 2005