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%I #10 Jul 28 2020 11:07:35
%S 3,5,131,137,151,157,337,347,547,557,839,859,1031,1051,1367,1439,1459,
%T 1567,1637,1657,1931,1951,2351,2531,2837,2857,3011,3119,3167,3209,
%U 3251,3257,3301,3307,3319,3391,3407,3449,3457,3547,3581,3631,3637,3659,3701
%N Primes that become a different prime under the mapping 3 <=> 5.
%H Robert Israel, <a href="/A180541/b180541.txt">Table of n, a(n) for n = 1..10000</a>
%H <a href="/index/Pri#primes">Index to Primes</a>, Primes that become a different prime under some mapping.
%p filter:= proc(n) local L,Lp,i,x;
%p if not isprime(n) then return false fi;
%p L:= convert(n,base,10);
%p Lp:= subs([3=5,5=3],L);
%p if L=Lp then return false fi;
%p isprime(add(Lp[i]*10^(i-1),i=1..nops(Lp)))
%p end proc:
%p select(filter, [seq(i,i=3..10000,2)]); # _Robert Israel_, Jul 28 2020
%t fQ[n_] := Block[{id = IntegerDigits@n}, (MemberQ[id, 3] || MemberQ[id, 5]) && PrimeQ[ FromDigits[ id /. {3 -> 5, 5 -> 3}] ]]; Select[ Prime@ Range@ 550, fQ]
%Y Cf. A171026, 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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