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A092911 Numbers all of whose divisors can be formed using their digits. Divisor digits are a subset of the digits of the number. 4
1, 11, 13, 17, 19, 31, 41, 61, 71, 101, 103, 107, 109, 113, 121, 125, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 241, 251, 271, 281, 311, 313, 317, 331, 401, 419, 421, 431, 461, 491, 521, 541, 571 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

All primes containing 1 are members.

Sequence is a subset of A011531. The first nonprime members of the sequence are 1, 121, 125, 1207, 1255, 1379, 10201, 10379, 11009, 11209, 12419, 12709, 12755, ... - R. J. Mathar, Jul 26 2007

LINKS

Table of n, a(n) for n=1..50.

EXAMPLE

131 is a member. 143 is not a member as the divisor 11 contains two ones.

MAPLE

isA092911 := proc(n) local digs, digsleft, divs, d, i, j ; digs := convert(n, base, 10) ; divs := numtheory[divisors](n) ; for i from 1 to nops(divs) do digsleft := digs ; d := convert(op(i, divs), base, 10) ; for j in d do if member(j, digsleft, 'jposit') then digsleft := subsop(jposit=NULL, digsleft) ; else RETURN(false) ; fi ; od ; od ; RETURN(true) ; end: for n from 1 to 600 do if isA092911(n) then printf("%d, ", n) ; fi ; od ; # R. J. Mathar, Jul 26 2007

CROSSREFS

Cf. A062634, A092912.

Sequence in context: A003626 A154981 A092912 * A062634 A239058 A208270

Adjacent sequences:  A092908 A092909 A092910 * A092912 A092913 A092914

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy, Mar 14 2004

EXTENSIONS

Corrected and extended by R. J. Mathar, Jul 26 2007

STATUS

approved

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Last modified May 26 13:05 EDT 2019. Contains 323586 sequences. (Running on oeis4.)