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A103677
Numbers m such that in binary representation m! doesn't contain 5!.
5
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, 46, 53, 58, 65
OFFSET
1,3
COMMENTS
Conjecture: there are no further terms;
complement of A103676: A103673(a(n))=0, A103673(A103676(n))=1.
PROG
(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
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Feb 12 2005
STATUS
approved