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A061461 Primes which produce primes when the leading digit is moved to the end. 4
2, 3, 5, 7, 11, 13, 17, 31, 37, 71, 73, 79, 97, 101, 103, 107, 113, 127, 131, 149, 157, 163, 181, 191, 197, 199, 307, 311, 317, 331, 337, 359, 367, 373, 701, 709, 719, 727, 733, 739, 757, 761, 787, 797, 907, 919, 937, 941, 947, 971, 983, 991, 1013, 1019 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

EXAMPLE

127 becomes 271 which is also a prime.

MAPLE

R:= 2, 3, 5, 7:

for d from 1 to 3 do

  for i in [1, 3, 7, 9] do

    for x from 1 to 10^d-1 by 2 do

      y:= i*10^d+x;

      if isprime(y) and isprime(10*x+i) then R:= R, y fi

od od od:

R; # Robert Israel, Aug 05 2020

CROSSREFS

Cf. A061459, A061460 (squares and cubes instead of primes).

Sequence in context: A086498 A211655 A055387 * A069706 A007500 A090933

Adjacent sequences:  A061458 A061459 A061460 * A061462 A061463 A061464

KEYWORD

nonn,base,easy

AUTHOR

Amarnath Murthy, May 04 2001

EXTENSIONS

More terms from Larry Reeves (larryr(AT)acm.org), May 25 2001

STATUS

approved

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Last modified January 21 03:58 EST 2022. Contains 350473 sequences. (Running on oeis4.)