A309671 Primes prime(m) such that G = prime(m-1)# - prime(m) is prime.

7, 11, 13, 17, 23, 83, 89, 97, 151, 373, 433, 857, 4013, 8821, 12959

Offset: 1

Author

Mohamed Sami Gattoufi, Aug 11 2019

Keywords

• nonn
• more

Comments

G = prime(n-1)# - prime(n) where G is a prime is a special case of A090188 where (k=1).

Examples

			7 is a term because 23 = 2*3*5 - 7 is prime.
		

Crossrefs

Cf. A002110, A065314, A060882, A096649, A090188, A065316.

Programs

PARI

primo(p) = my(ip=primepi(p)); factorback(primes(ip)); \\ A002110
isok(p) = isprime(p) && isprime(primo(precprime(p-1)) - p);