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A069791
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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.
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0
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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
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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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.
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MATHEMATICA
| Select[Prime[Range[PrimePi[1000]+1, PrimePi[9999]]], PrimeQ[FromDigits[Rest[Most[IntegerDigits[#]]]]]&] (* From Harvey P. Dale, Jan 04 2011 *)
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CROSSREFS
| Cf. A069686.
Sequence in context: A015160 A102925 A024020 * A167846 A088290 A179032
Adjacent sequences: A069788 A069789 A069790 * A069792 A069793 A069794
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KEYWORD
| base,nonn,changed
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AUTHOR
| Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Apr 09 2002
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EXTENSIONS
| Corrected by T. D. Noe (noe(AT)sspectra.com), Nov 01 2006
Corrected and extended by Harvey P. Dale, Jan 04 2011
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