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A103681 Numbers m such that in binary representation m! doesn't contain 7!. 5
0, 1, 2, 3, 4, 5, 6, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Complement of A103680: A103675(a(n))=0, A103675(A103680(n))=1.

Last term is probably 5153, since all numbers from 5154 to 5*10^5 do not belong to the sequence. - Giovanni Resta, Apr 07 2013

LINKS

Table of n, a(n) for n=1..72.

Index entries for sequences related to factorial numbers

Index entries for sequences related to binary expansion of n

PROG

(PARI) is(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(0))); 1 \\ Charles R Greathouse IV, Apr 07 2013

CROSSREFS

Cf. A102730, A036603, A007088, A000142, A103677, A103679.

Sequence in context: A297165 A245606 A269864 * A319824 A039265 A073599

Adjacent sequences:  A103678 A103679 A103680 * A103682 A103683 A103684

KEYWORD

base,nonn

AUTHOR

Reinhard Zumkeller, Feb 12 2005

STATUS

approved

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Last modified November 29 23:27 EST 2020. Contains 338780 sequences. (Running on oeis4.)