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A103169
Start of seven consecutive primes whose digit reversals are also prime.
4
2, 727, 733, 1193, 1201, 1213, 1217, 11897, 18719, 79379, 125627, 334759, 334771, 743989, 910909, 920957, 928429, 941449, 1093571, 1215079, 1407181, 1466533, 1518863, 1648553, 1770829, 3170743, 3300593, 7321943, 7682687, 7755581
OFFSET
1,1
EXAMPLE
1193, 1201, 1213, 1217, 1223, 1229 and 1231 are consecutive primes.
Their digit reversals, 3911, 1021, 3121, 7121, 3221, 9221 and 1321, are all prime.
MATHEMATICA
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 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Labos Elemer, Jan 31 2005
EXTENSIONS
Edited by David Wasserman, Sep 05 2006
STATUS
approved