OFFSET
1,1
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
Index to Primes, Primes that become a different prime under some mapping.
MATHEMATICA
fQ[n_] := Block[{id = IntegerDigits@n}, (MemberQ[id, 4] || MemberQ[id, 6]) && PrimeQ[ FromDigits[ id /. {4 -> 6, 6 -> 4}] ]]; Select[ Prime@ Range@ 440, fQ]
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 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Zak Seidov and Robert G. Wilson v, Sep 09 2010
STATUS
approved