A069791 Primes which yield primes each time the process of removing two outermost digits is carried out until finally a two digit prime (possibly with a leading 0) is obtained.
1021, 1031, 1033, 1039, 1051, 1117, 1171, 1193, 1231, 1237, 1291, 1297, 1319, 1373, 1433, 1439, 1471, 1531, 1597, 1613, 1619, 1733, 1831, 1973, 1979, 2027, 2029, 2039, 2053, 2111, 2113, 2131, 2137, 2179, 2237, 2239, 2293, 2297, 2311, 2371
Offset: 1
Examples
101737 is a member as the number obtained by removing the first and the last digit 0173 is a prime and further removing the first and the last digit gives another prime 17.
Crossrefs
Cf. A069686.
Programs
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Mathematica
Select[Prime[Range[PrimePi[1000]+1, PrimePi[9999]]], PrimeQ[FromDigits[Rest[Most[IntegerDigits[#]]]]]&] (* Harvey P. Dale, Jan 04 2011 *)
Extensions
Corrected by T. D. Noe, Nov 01 2006
Corrected and extended by Harvey P. Dale, Jan 04 2011