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%I #19 Nov 22 2020 03:07:17
%S 1,11,13,17,19,31,41,61,71,101,103,107,109,113,121,125,127,131,137,
%T 139,143,149,151,157,163,167,173,179,181,187,191,193,197,199,211,241,
%U 251,271,281,311,313,317,331,341,401,419,421,431,451,461,491,521,541,571
%N Numbers k all of whose divisors contain only digits that occur at least once in k.
%C All primes containing the digit 1 are terms.
%H Amiram Eldar, <a href="/A092912/b092912.txt">Table of n, a(n) for n = 1..10000</a>
%e 131 is a term. 143 is also a term with divisors 1,11,13,143.
%p 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
%t Do[a = IntegerDigits[n]; b = Union @@ IntegerDigits[Divisors[n]]; If[Intersection[a, b] == b, Print[n]], {n, 1, 200}] (* _Ryan Propper_, Jul 19 2005 *)
%o (PARI) is_A092912(n)=!setminus(Set(concat(apply(digits,divisors(n)))),Set(digits(n))) \\ _M. F. Hasler_, Mar 09 2014
%Y Cf. A062634, A092911.
%K base,nonn
%O 1,2
%A _Amarnath Murthy_, Mar 14 2004
%E Corrected and extended by _Ryan Propper_, Jul 19 2005
%E More terms from _R. J. Mathar_, Jul 26 2007
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