Shanmuga Subramanian - cp's OEIS frontend

User: Shanmuga Subramanian

Shanmuga Subramanian has authored 2 sequences.

A246965 Numbers n such that 19*n-(n+19) is a prime.

2, 4, 5, 6, 7, 11, 12, 14, 15, 16, 21, 25, 26, 27, 29, 30, 32, 34, 37, 39, 40, 41, 44, 46, 47, 49, 50, 54, 55, 60, 62, 65, 67, 69, 71, 72, 77, 81, 84, 85, 89, 90, 91, 92, 96, 105, 106, 107, 111, 112, 116, 117, 120, 124, 127, 131, 132, 134, 135, 137, 145, 146

Offset: 1

Shanmuga Subramanian, Sep 08 2014

nonn

			17 = (19*2)-(19+2) is prime, so 2 is a term.

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

Select[Range[150],PrimeQ[18#-19]&] (* Harvey P. Dale, Jun 10 2016 *)

lista(nn) = {for (n=1, nn, if (isprime(18*n-19), print1(n, ", ")););} \\ Michel Marcus, Sep 09 2014

PHP
```
for($num=1;$num
				
```

[n for n in (2..200) if is_prime(18*n-19)] # Bruno Berselli, Sep 09 2014

a(n) = A138918(n)+1.

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

Original entry on oeis.org

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

Shanmuga Subramanian, Sep 08 2014

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

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

Cf. A109308.

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

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

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);
}

cp's OEIS Frontend

User: Shanmuga Subramanian

A246965 Numbers n such that 19*n-(n+19) is a prime.

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