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A078239 a(n) = smallest multiple of n using only prime digits, with a(n) = 0 if there are none.

%I A078239 #6 Feb 12 2018 21:06:32
%S A078239 2,2,3,32,5,72,7,32,27,0,22,72,52,252,75,32,255,72,57,0,252,22,23,72,
%T A078239 25,52,27,252,232,0,372,32,33,272,35,72,37,532,273,0,533,252,2322,352,
%U A078239 225,322,235,2352,735,0,255,52,53,2322,55,2352,57,232,2537,0,732,372,252,2752,325,2772,335,272
%N A078239 a(n) = smallest multiple of n using only prime digits, with a(n) = 0 if there are none.
%C A078239 Besides multiples of 10, 625 and its odd multiples have a(n)=0. - _Robert Israel_, Feb 12 2018
%H A078239 Robert Israel, <a href="/A078239/b078239.txt">Table of n, a(n) for n = 1..10000</a>
%p A078239 f := proc (n) local k, k10, j;
%p A078239   if n mod 10 = 0 or n mod 625 = 0 then return 0 end if;
%p A078239   k10 := select(t -> member(t*n mod 10, {2, 3, 5, 7}), [$1 .. 9]);
%p A078239   for j from 0 do
%p A078239     for k in k10 do
%p A078239       if convert(convert((10*j+k)*n, base, 10), set) subset {2, 3, 5, 7}
%p A078239       then return (10*j+k)*n
%p A078239       fi
%p A078239 od od
%p A078239 end proc:
%p A078239 map(f, [$1..100]; # _Robert Israel_, Feb 12 2018
%K A078239 base,easy,nonn
%O A078239 1,1
%A A078239 _Amarnath Murthy_, Nov 23 2002
%E A078239 Edited and more terms from _Robert Israel_, Feb 12 2018