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%I #8 Dec 16 2021 19:07:25
%S 353,373,727,757,32323,33533,35353,72227,72727,75557,77377,3222223,
%T 3223223,3233323,3337333,3353533,3553553,3773773,7722277,7733377,
%U 7772777,322222223,322323223,323222323,323232323,323333323,333535333
%N Palindromic primes with just two distinct prime digits.
%t Select[ Range[ 1, 780000000, 2 ], PrimeQ[ # ] && Length[ Union[ IntegerDigits[ # ] ] ] == 2 && IntegerDigits[ # ] == Reverse[ IntegerDigits[ # ] ] && Position[ IntegerDigits[ # ], 0 ] == {} && Position[ IntegerDigits[ # ], 1 ] == {} && Position[ IntegerDigits[ # ], 4 ] == {} && Position[ IntegerDigits[ # ], 6 ] == {} && Position[ IntegerDigits[ # ], 8 ] == {} && Position[ IntegerDigits[ # ], 9 ] == {} & ]
%t Select[Prime[Range[18*10^6]],PalindromeQ[#]&&AllTrue[ IntegerDigits[ #],PrimeQ] && Length[ Union[ IntegerDigits[ #]]] ==2&] (* _Harvey P. Dale_, Dec 16 2021 *)
%Y Cf. A056730.
%K nonn,base
%O 1,1
%A _Robert G. Wilson v_, Dec 18 2000