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A092912
Numbers k all of whose divisors contain only digits that occur at least once in k.
3
1, 11, 13, 17, 19, 31, 41, 61, 71, 101, 103, 107, 109, 113, 121, 125, 127, 131, 137, 139, 143, 149, 151, 157, 163, 167, 173, 179, 181, 187, 191, 193, 197, 199, 211, 241, 251, 271, 281, 311, 313, 317, 331, 341, 401, 419, 421, 431, 451, 461, 491, 521, 541, 571
OFFSET
1,2
COMMENTS
All primes containing the digit 1 are terms.
LINKS
EXAMPLE
131 is a term. 143 is also a term with divisors 1,11,13,143.
MAPLE
isA092912 := proc(n) local digs, divs, d, i, j ; digs := convert(n, base, 10) ; divs := numtheory[divisors](n) ; for i from 1 to nops(divs) do d := convert(op(i, divs), base, 10) ; for j in d do if not j in digs then RETURN(false) ; fi ; od ; od ; RETURN(true) ; end: for n from 1 to 700 do if isA092912(n) then printf("%d, ", n) ; fi ; od ; # R. J. Mathar, Jul 26 2007
MATHEMATICA
Do[a = IntegerDigits[n]; b = Union @@ IntegerDigits[Divisors[n]]; If[Intersection[a, b] == b, Print[n]], {n, 1, 200}] (* Ryan Propper, Jul 19 2005 *)
PROG
(PARI) is_A092912(n)=!setminus(Set(concat(apply(digits, divisors(n)))), Set(digits(n))) \\ M. F. Hasler, Mar 09 2014
CROSSREFS
Sequence in context: A155071 A003626 A154981 * A092911 A062634 A239058
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Mar 14 2004
EXTENSIONS
Corrected and extended by Ryan Propper, Jul 19 2005
More terms from R. J. Mathar, Jul 26 2007
STATUS
approved