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A048381 Numbers k such that replacing each nonzero digit d with the d-th prime (replacing each 0 digit with a 1) yields a prime.

%I A048381 #17 Oct 13 2019 02:31:39
%S A048381 1,2,3,4,5,6,7,8,9,12,15,19,20,24,25,26,27,32,39,40,42,48,52,57,59,60,
%T A048381 64,68,72,79,80,82,84,86,92,95,100,105,106,112,114,116,122,125,130,
%U A048381 134,140,144,145,146,148,150,152,160,164,166,167,168,169,176
%N A048381 Numbers k such that replacing each nonzero digit d with the d-th prime (replacing each 0 digit with a 1) yields a prime.
%H A048381 Robert Israel, <a href="/A048381/b048381.txt">Table of n, a(n) for n = 1..10000</a>
%e A048381 176 = (1)(7)(6) -> (2)(17)(13) = 21713, which is a prime, so 176 is in the sequence.
%p A048381 filter := proc(n) local L;
%p A048381   L:= convert(n,base,10);
%p A048381   L:= subs([0=1,seq(i=ithprime(i),i=1..9)],L);
%p A048381   L:= map(t -> op(convert(t,base,10)), L);
%p A048381   isprime(add(L[i]*10^(i-1),i=1..nops(L)))
%p A048381 end proc:
%p A048381 select(filter, [$1..1000]); # _Robert Israel_, Oct 16 2018
%Y A048381 Cf. A048380, A048382.
%K A048381 nonn,base
%O A048381 1,2
%A A048381 _Patrick De Geest_, Mar 15 1999
%E A048381 Offset corrected by _Robert Israel_, Oct 16 2018