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A030150
Palindromic primes in which parity of digits alternates.
2
2, 3, 5, 7, 101, 181, 383, 727, 787, 929, 10301, 10501, 12721, 14341, 14741, 16361, 16561, 18181, 30103, 30703, 32323, 34543, 36563, 38183, 38783, 70507, 72727, 74747, 76367, 78787, 90709, 94349, 94949, 96769, 98389, 1074701
OFFSET
1,1
LINKS
MATHEMATICA
altQ[n_] := n < 10 || Union[Total /@ Partition[ Mod[ IntegerDigits@ n, 2], 2, 1]] == {1}; palQ[n_] := Block[{d = IntegerDigits[n]}, d == Reverse@ d]; Select[ Prime@ Range@ 10000, palQ[#] && altQ[#] &] (* Giovanni Resta, Aug 16 2018 *)
Join[{2, 3, 5, 7}, Select[Prime[Range[85000]], PalindromeQ[#]&&Union[Total/@Partition[ Boole[ EvenQ/@IntegerDigits[#]], 2, 1]]=={1}&]] (* Harvey P. Dale, Jul 10 2023 *)
CROSSREFS
KEYWORD
nonn,base
STATUS
approved