1,2

Seven terms found and primes proved by PrimeForm ([N-1, Brillhart-Lehmer-Selfridge]). p(1282)#^4 + 1 has 18042 decimal digits. There are no more terms <= 2810.

Table of n, a(n) for n=1..7.

As primorial(2)^4 + 1 = (3*2)^4 + 1 = 1297 is prime, 2 is a term.

Cf. A092061.

Sequence in context: A322520 A018279 A307459 * A203103 A308164 A173352

Adjacent sequences: A133831 A133832 A133833 * A133835 A133836 A133837

hard,nonn

Rick L. Shepherd, Sep 26 2007

approved