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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.
0
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
1,1
EXAMPLE
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.
MATHEMATICA
Select[Prime[Range[PrimePi[1000]+1, PrimePi[9999]]], PrimeQ[FromDigits[Rest[Most[IntegerDigits[#]]]]]&] (* Harvey P. Dale, Jan 04 2011 *)
CROSSREFS
Cf. A069686.
Sequence in context: A102925 A216115 A024020 * A167846 A303918 A371378
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Apr 09 2002
EXTENSIONS
Corrected by T. D. Noe, Nov 01 2006
Corrected and extended by Harvey P. Dale, Jan 04 2011
STATUS
approved