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%I #12 Feb 28 2022 17:31:10
%S 41,47,61,67,347,367,401,419,431,461,463,467,491,601,619,631,641,643,
%T 647,691,947,967,1049,1069,1409,1427,1447,1493,1499,1609,1627,1667,
%U 1693,1699,1847,1867,2141,2161,2417,2459,2467,2477,2617,2647,2659,2677,3041
%N Primes that become a different prime under the mapping 4 <=> 6.
%H Harvey P. Dale, <a href="/A180547/b180547.txt">Table of n, a(n) for n = 1..1000</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, 6]) && PrimeQ[ FromDigits[ id /. {4 -> 6, 6 -> 4}] ]]; Select[ Prime@ Range@ 440, fQ]
%t dpQ[n_]:=(DigitCount[n,10,4]>0 || DigitCount[n,10,6]>0)&&PrimeQ[ FromDigits[ IntegerDigits[n]/.{4->a,6->b}/.{a->6,b->4}]]; Select[ Prime[ Range[500]],dpQ](* _Harvey P. Dale_, Feb 28 2022 *)
%Y Cf. A171032, 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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