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A103675
a(n) = 1 if the binary representation of n! contains 7! (bit string "1001110110000"), otherwise a(n) = 0.
6
0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0
OFFSET
0,1
COMMENTS
a(A103680(n)) = 1, a(A103681(n)) = 0.
Probably a(5153) is the last zero term. a(n) = 1 for n from 5154 to 5*10^5. - Giovanni Resta, Apr 07 2013
PROG
(PARI) a(n)=n=n!; while(n>5039, my(e=valuation(n, 2), e1=valuation((n>>=e)+1, 2)); n>>=e1; if(e>3 && e1==2 && bitand(n, 127)==78, return(1))); 0 \\ Charles R Greathouse IV, Apr 07 2013
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Reinhard Zumkeller, Feb 12 2005
EXTENSIONS
Name edited by Antti Karttunen, Dec 24 2018
STATUS
approved