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A092912
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Numbers k all of whose divisors contain only digits that occur at least once in k.
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3
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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
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OFFSET
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1,2
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COMMENTS
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All primes containing the digit 1 are terms.
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LINKS
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EXAMPLE
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131 is a term. 143 is also a term with divisors 1,11,13,143.
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MAPLE
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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
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MATHEMATICA
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Do[a = IntegerDigits[n]; b = Union @@ IntegerDigits[Divisors[n]]; If[Intersection[a, b] == b, Print[n]], {n, 1, 200}] (* Ryan Propper, Jul 19 2005 *)
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PROG
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(PARI) is_A092912(n)=!setminus(Set(concat(apply(digits, divisors(n)))), Set(digits(n))) \\ M. F. Hasler, Mar 09 2014
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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