A138696 Primes p such that 30*p-1, 30*p+1 and 36*p-1, 36*p+1 are twin primes.

2, 5, 457, 1013, 2683, 5413, 46307, 51287, 67433, 99223, 116443, 146603, 149837, 159017, 172373, 181277, 187987, 199523, 248477, 249503, 259163, 278903, 279337, 286333, 293893, 294803, 304813, 312527, 315037, 335743, 379433, 392593, 393713

Offset: 1

Author

Vladimir Joseph Stephan Orlovsky, May 15 2008

Keywords

• nonn
• easy

Examples

			30*2-1=59, 30*2+1=61; 36*2-1=71, 36*2+1=73;
30*5-1=149, 30*5+1=151; 36*5-1=179, 36*5+1=181; ...
		

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..2000

Programs

Magma

[p: p in PrimesUpTo(1000000)| IsPrime(30*p-1) and IsPrime(30*p+1) and IsPrime(36*p-1) and IsPrime(36*p+1)]; // Vincenzo Librandi, Nov 24 2010

Mathematica

a=30;b=36;Select[Prime[Range[14^4]],PrimeQ[a*#-1]&&PrimeQ[a*#+1]&&PrimeQ[b*#-1]&&PrimeQ[b*#+1]&]
Select[Prime[Range[35000]],AllTrue[Flatten[{30#+{1,-1},36#+{1,-1}}], PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Jan 20 2015 *)

Extensions

More terms from Vincenzo Librandi, Apr 01 2010