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Primes which produce primes when the leading digit is moved to the end.
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%I #13 Nov 13 2023 10:01:55

%S 2,3,5,7,11,13,17,31,37,71,73,79,97,101,103,107,113,127,131,149,157,

%T 163,181,191,197,199,307,311,317,331,337,359,367,373,701,709,719,727,

%U 733,739,757,761,787,797,907,919,937,941,947,971,983,991,1013,1019

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

%H Robert Israel, <a href="/A061461/b061461.txt">Table of n, a(n) for n = 1..10000</a>

%e 127 becomes 271 which is also a prime.

%p R:= 2,3,5,7:

%p for d from 1 to 3 do

%p for i in [1,3,7,9] do

%p for x from 1 to 10^d-1 by 2 do

%p y:= i*10^d+x;

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

%p od od od:

%p R; # _Robert Israel_, Aug 05 2020

%t Select[Prime[Range[200]],PrimeQ[FromDigits[RotateLeft[IntegerDigits[#]]]]&] (* _Paolo Xausa_, Nov 13 2023 *)

%Y Cf. A234901.

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

%K nonn,base,easy

%O 1,1

%A _Amarnath Murthy_, May 04 2001

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