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A116519
Primes which stay prime when the end digits (on both sides) are repeated once.
1
131, 139, 163, 167, 193, 211, 227, 251, 269, 277, 281, 331, 337, 353, 359, 463, 541, 563, 571, 593, 653, 673, 761, 769, 797, 821, 881, 937, 983, 1031, 1093, 1097, 1153, 1279, 1301, 1427, 1429, 1459, 1483, 1549, 1609, 1693, 1783, 1787, 1789, 1879, 1931
OFFSET
1,1
LINKS
EXAMPLE
The derived numbers 11311,11399,11633,11933,22111,22277,...are also primes.
MATHEMATICA
FromDigits /@ Select[IntegerDigits@Prime@Range[400], PrimeQ@FromDigits@Flatten@{First@#, #, Last@#} &] - Giovanni Resta, Apr 04 2006
CROSSREFS
Sequence in context: A050671 A095317 A357075 * A139646 A139970 A159256
KEYWORD
nonn,base
AUTHOR
Lekraj Beedassy, Mar 25 2006
EXTENSIONS
More terms from Giovanni Resta, Apr 04 2006
STATUS
approved