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

1,1

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

Links

Table of n, a(n) for n=1..3.

Example

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

Mathematica

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

Crossrefs

Cf. A096345, A096342, A120850.

Sequence in context: A201112 A250156 A197112 * A302332 A344147 A198483

Adjacent sequences: A120848 A120849 A120850 * A120852 A120853 A120854

Keyword

nonn,bref

Author

Carlos Alves, Jul 08 2006

Extensions

The next term is too large to include.

Status

approved