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A103169 Start of seven consecutive primes whose digit reversals are also prime. 4

%I

%S 2,727,733,1193,1201,1213,1217,11897,18719,79379,125627,334759,334771,

%T 743989,910909,920957,928429,941449,1093571,1215079,1407181,1466533,

%U 1518863,1648553,1770829,3170743,3300593,7321943,7682687,7755581

%N Start of seven consecutive primes whose digit reversals are also prime.

%e 1193, 1201, 1213, 1217, 1223, 1229 and 1231 are consecutive primes.

%e Their digit reversals, 3911, 1021, 3121, 7121, 3221, 9221 and 1321, are all prime.

%t With[{s = Prime@ Range[10^6]}, IntegerReverse /@ Flatten@ Map[Take[#, Length@ # - 6] &, DeleteCases[SplitBy[Map[IntegerReverse, s], PrimeQ], k_ /; Or[CompositeQ@ First@ k, Length@ k < 7]]]] (* _Michael De Vlieger_, Jul 24 2017 *)

%Y Cf. A007500, A103170, A103171, A103172.

%K base,nonn

%O 1,1

%A _Labos Elemer_, Jan 31 2005

%E Edited by _David Wasserman_, Sep 05 2006

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Last modified November 11 22:31 EST 2019. Contains 329046 sequences. (Running on oeis4.)