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A113838
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Palindromes sandwiched between twin primes.
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0
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4, 6, 282, 828, 858, 2112, 21012, 21612, 23832, 26262, 26862, 28182, 80208, 81018, 82728, 84348, 89598, 89898, 240042, 246642, 270072, 276672, 2035302, 2109012, 2136312, 2155512, 2182812, 2422242, 2428242, 2460642, 2499942, 2529252
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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EXAMPLE
| 282 is a palindrome and 281 and 283 are twin primes.
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MATHEMATICA
| palQ[n_]:= n == FromDigits@Reverse@IntegerDigits@n; lst={}; Do[If[palQ[n] && PrimeQ[n-1] && PrimeQ[n+1], AppendTo[lst, n]], {n, 2, 10^7, 2}]; lst
palQ[n_]:=Module[{idn=IntegerDigits[n]}, idn==Reverse[idn]]; Mean[#]&/@ Select[ Select[ Partition[Prime[Range[190000]], 2, 1], Last[#]-First[#] == 2&], palQ[Mean[#]]&] (* From Harvey P. Dale, Jan 18 2012 *)
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CROSSREFS
| Sequence in context: A081970 A076098 A141568 * A056831 A027717 A035481
Adjacent sequences: A113835 A113836 A113837 * A113839 A113840 A113841
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KEYWORD
| base,nonn
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AUTHOR
| Giovanni Resta (g.resta(AT)iit.cnr.it), Jan 24 2006
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