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A028981 Primes p such that p+1 is palindromic. 1
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..750

Patrick De Geest, World!Of Palindromic Primes

MATHEMATICA

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 *)

CROSSREFS

Cf. A027713.

Sequence in context: A120804 A092066 A224904 * A223035 A096843 A052016

Adjacent sequences:  A028978 A028979 A028980 * A028982 A028983 A028984

KEYWORD

nonn,base

AUTHOR

Patrick De Geest

STATUS

approved

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Last modified July 28 14:19 EDT 2021. Contains 346335 sequences. (Running on oeis4.)