A096902 Numbers n such that 3*prime(n) + 2*prime(n+1) is prime.

2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 16, 18, 20, 24, 26, 27, 30, 31, 37, 38, 40, 46, 48, 50, 55, 56, 58, 60, 62, 63, 64, 66, 67, 70, 71, 72, 73, 74, 78, 81, 85, 88, 89, 92, 95, 98, 102, 109, 113, 114, 116, 120, 121, 122, 130, 133, 134, 135, 136, 140, 144, 147, 148, 152

Offset: 1

Author

Ray Chandler, Jul 31 2004

Keywords

• nonn

Examples

			a(3)=4 since 3*prime(4)+2*prime(5) = 3*7 + 2*11 = 43 is prime.
		

Links

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

Crossrefs

Cf. A096218 for resulting primes.

Programs

Maple

select(n -> isprime(3*ithprime(n)+2*ithprime(n+1)), [$1..200]); # Robert Israel, Mar 11 2020

Mathematica

Position[Partition[Prime[Range[200]],2,1],?(PrimeQ[3#[[1]]+2#[[2]]]&),{1},Heads->False]//Flatten (* _Harvey P. Dale, Apr 23 2016 *)