A120851 Numbers n such that n is prime and is equal to the product of the first k primes minus the sum of the first k primes, for some k.

193, 29989, 13082761331669749

Offset: 1

Author

Carlos Alves, Jul 08 2006

Keywords

• nonn
• bref

Comments

It is in the spirit of A096345 (only for 2 consecutive primes).

The corresponding values of k are 4, 6, 14, 548, 1190, ... a(4) = 2.452... * 10^1691, a(5) = 1.263... x 10^4142. - Amiram Eldar, Dec 19 2018

Examples

			193 = -(2+3+5+7)+(2*3*5*7) and 193 is prime.
		

Crossrefs

Cf. A096345, A096342, A120850.

Programs

Mathematica

tb = {}; Do[pq = -Plus @@ Prime[Range[1, k]] + Times @@ Prime[Range[1, k]]; If[PrimeQ[pq], AppendTo[tb, pq]], {k, 1, 200}]; tb

Extensions

The next term is too large to include.