A061461 Primes which produce primes when the leading digit is moved to the end.

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

Offset: 1

Author

Amarnath Murthy, May 04 2001

Keywords

• nonn
• base
• easy

Examples

			127 becomes 271 which is also a prime.
		

Links

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

Crossrefs

Cf. A234901.

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

Programs

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

Mathematica

Select[Prime[Range[200]],PrimeQ[FromDigits[RotateLeft[IntegerDigits[#]]]]&] (* Paolo Xausa, Nov 13 2023 *)

Extensions

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