A246944 Prime numbers p with property that when the first digit is shifted to the last digit, we obtain a prime greater than p.

13, 17, 37, 79, 113, 127, 131, 149, 157, 163, 181, 191, 197, 199, 337, 359, 367, 373, 787, 797, 1117, 1123, 1129, 1151, 1153, 1181, 1187, 1193, 1201, 1213, 1231, 1237, 1259, 1279, 1297, 1301, 1319, 1327, 1367, 1409, 1423, 1427, 1439, 1459, 1483, 1487, 1493

Offset: 1

Author

Shanmuga Subramanian, Sep 08 2014

Keywords

• nonn
• base

Examples

			13: when 1 is shifted to last it becomes 31.
		

Links

• Jens Kruse Andersen, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A109308.

Programs

Mathematica

fdlQ[n_]:=Module[{c=FromDigits[RotateLeft[IntegerDigits[n]]]},PrimeQ[c] && c>n]; Select[Prime[Range[300]],fdlQ] (* Harvey P. Dale, Jun 06 2018 *)

PARI

move(n)=n=Vec(Str(n));N=List();for(i=2,#n,listput(N,n[i]));listput(N,n[1]);return(eval(concat(N)));
forprime(p=2,1000,if(isprime(move(p))&&move(p)>p,print1(p,","))) \\ Edward Jiang, Sep 08 2014

PHP

function number_firsttolast($a)
{
$b=str_split($a);
$c=count($b);
for($i=1;$i<$c;$i++)
{
  $d=$d.$b[$i];
}
$e=$d.$b[0];
return ($e);
}