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%I #11 Oct 30 2023 17:11:58
%S 41,43,71,73,149,179,241,271,349,379,401,409,419,433,439,443,461,541,
%T 571,643,673,701,709,719,733,739,761,773,941,971,1249,1279,1409,1423,
%U 1433,1453,1459,1471,1483,1489,1549,1579,1709,1723,1733,1741,1753,1759
%N Primes that become a different prime under the mapping 4 <=> 7.
%H Robert Price, <a href="/A180548/b180548.txt">Table of n, a(n) for n = 1..2779</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, 4] || MemberQ[id, 7]) && PrimeQ[ FromDigits[ id /. {4 -> 7, 7 -> 4}] ]]; Select[ Prime@ Range@ 300, fQ]
%Y Cf. A171038, A175791, A180517 thru A180559, A175789, A180560, A180561.
%K base,nonn
%O 1,1
%A _Zak Seidov_ and _Robert G. Wilson v_, Sep 09 2010