%I #11 Oct 30 2023 11:14:46
%S 3,7,13,17,31,37,43,47,71,73,103,107,137,139,163,167,173,179,193,197,
%T 223,227,233,277,337,347,353,379,383,439,463,467,479,613,617,643,647,
%U 739,743,757,773,787,823,827,853,857,883,887,1093,1097,1213,1217,1321
%N Primes that become a different prime under the mapping 3 <=> 7.
%H Robert Price, <a href="/A180543/b180543.txt">Table of n, a(n) for n = 1..3168</a>
%H <a href="/index/Pri#primes">Index to Primes</a>, Primes that become a different prime under some mapping.
%t fQ[n_] := Block[{id = IntegerDigits@n}, (MemberQ[id, 3] || MemberQ[id, 7]) && PrimeQ[ FromDigits[ id /. {3 -> 7, 7 -> 3}] ]]; Select[ Prime@ Range@ 250, fQ]
%Y Cf. A171037, A175791, A180517 thru A180559, A175789, A180560, A180561.
%K base,nonn
%O 1,1
%A _Zak Seidov_ and _Robert G. Wilson v_, Sep 09 2010
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