A108270 Numbers n such that n*n! + (smallest prime >= n) is prime.

1, 4, 6, 8, 30, 40, 164, 176, 189, 218, 370, 597, 603, 1473, 2176, 2436, 2548, 2732, 4758, 5574

Offset

1,2

Comments

Note that Maple, PARI etc. have different notions of what "next prime" means!

Links

Table of n, a(n) for n=1..20.

Formula

A096986 INTERSECT A018252. - R. J. Mathar, Aug 13 2007

Mathematica

Select[Range[5600], PrimeQ[# (#!) +NextPrime[#-1]]&] (* Harvey P. Dale, Oct 07 2019 *)

Prog

(PARI) for(x=1, 1000, if(isprime(x*x!+nextprime(x)), print1(x, ", ")))

Crossrefs

Cf. A096986.

Sequence in context: A366557 A089330 A227553 * A019161 A291718 A137026

Adjacent sequences: A108267 A108268 A108269 * A108271 A108272 A108273

Keyword

nonn,more

Author

Jorge Coveiro, Jul 24 2006

Extensions

a(11)-a(20) from Donovan Johnson, Dec 13 2008

Status

approved