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A028981
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Primes p such that p+1 is palindromic.
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1
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2, 3, 5, 7, 43, 211, 241, 251, 271, 281, 433, 443, 463, 827, 857, 877, 887, 2111, 2221, 2441, 2551, 4003, 4663, 4993, 8117, 8447, 8887, 20101, 20201, 21011, 21211, 21611, 21911, 22621, 22721, 22921, 23131, 23431, 23531, 23831, 24841
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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palQ[n_] := Module[{idn = IntegerDigits[n + 1], len = Floor[IntegerLength[n + 1]/2]}, Take[idn, len] == Reverse[Take[idn, -len]]]; Select[Prime[Range[2800]], palQ] (* Harvey P. Dale, Nov 04 2011 *)
Select[Prime[Range[2800]], Reverse[x = IntegerDigits[# + 1]] == x &] (* Jayanta Basu, Jun 05 2013 *)
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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