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A105435 Primes which with a 1 prepended stay prime. 1
3, 7, 13, 31, 37, 67, 73, 79, 97, 103, 109, 151, 163, 181, 193, 223, 229, 277, 283, 307, 367, 373, 409, 433, 439, 487, 499, 523, 571, 601, 607, 613, 619, 709, 733, 787, 811, 823, 877, 907, 997, 1069, 1087, 1093, 1117, 1171, 1213, 1279, 1321, 1399, 1423, 1447 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

MAPLE

with(numtheory); for i from 1 to 500 do if isprime(10^(ceil(log[10](ithprime(i))))+ithprime(i)) then printf(`%d, `, ithprime(i)) fi: od: (Sellers)

MATHEMATICA

Select[ Prime[ Range[ 230]], PrimeQ[ FromDigits[ Join[{1}, IntegerDigits[ # ]]]] &] (from Robert G. Wilson v (rgwv(AT)rgwv.com), Apr 09 2005)

CROSSREFS

Cf. A023237.

Sequence in context: A049488 A136051 A100750 * A117708 A093431 A083520

Adjacent sequences:  A105432 A105433 A105434 * A105436 A105437 A105438

KEYWORD

nonn,base

AUTHOR

Lekraj Beedassy (blekraj(AT)yahoo.com), Apr 08 2005

EXTENSIONS

Corrected and extended by Robert G. Wilson v (rgwv(AT)rgwv.com) and James A. Sellers (sellersj(AT)math.psu.edu), Apr 09 2005

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Last modified February 16 21:04 EST 2012. Contains 205969 sequences.