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%I #8 Mar 06 2016 13:26:00
%S 5,7,53,59,73,79,251,271,353,359,373,379,509,569,571,653,673,709,751,
%T 769,1151,1171,1259,1279,1451,1471,1523,1579,1583,1723,1759,1783,2351,
%U 2371,2531,2549,2591,2731,2749,2791,3251,3271,3533,3539,3559,3593,3733
%N Primes that become a different prime under the mapping 5 <=> 7.
%H Harvey P. Dale, <a href="/A180552/b180552.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, 5] || MemberQ[id, 7]) && PrimeQ[ FromDigits[ id /. {5 -> 7, 7 -> 5}] ]]; Select[ Prime@ Range@ 550, fQ]
%Y Cf. A171039, 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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