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A103679
Numbers m such that in binary representation m! doesn't contain 6!.
5
0, 1, 2, 3, 4, 5, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 24, 25, 26, 27, 28, 29, 33, 34, 35, 36, 38, 39, 40, 41, 42, 44, 45, 46, 47, 48, 49, 50, 51, 52, 54, 56, 57, 59, 60, 61, 62, 63, 64, 66, 67, 68, 69, 70, 72, 73, 75, 76, 77, 78, 79, 80, 82, 83, 84, 85, 87
OFFSET
1,3
COMMENTS
Complement of A103678: A103674(a(n))=0, A103674(A103678(n))=1.
Last term is probably 802. No numbers between 803 and 500000 belong to the sequence. - Giovanni Resta, Apr 07 2013
MATHEMATICA
Select[Range[0, 100], SequenceCount[IntegerDigits[#!, 2], {1, 0, 1, 1, 0, 1, 0, 0, 0, 0}]==0&] (* Harvey P. Dale, Oct 12 2024 *)
PROG
(PARI) is(n)=n=n!; while(n>719, my(e=valuation(n, 2), e1=valuation((n>>=e)+1, 2)); n>>=e1; if(e>3 && e1==1 && bitand(n, 31)==22, return(0))); 1 \\ Charles R Greathouse IV, Apr 07 2013
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Feb 12 2005
STATUS
approved