A085146 Numbers k such that k!!!! + 1 is prime.

0, 1, 2, 4, 6, 18, 38, 56, 94, 118, 148, 286, 1358, 1480, 1514, 2680, 2846, 4078, 4288, 5612, 5680, 6440, 6586, 14614, 30972, 31690, 54406

Offset

1,3

Comments

The search for multifactorial primes started by Ray Ballinger is now continued by a team of volunteers on the website of Ken Davis (see link).

Links

Table of n, a(n) for n=1..27.

Ken Davis, Status of Search for Multifactorial Primes.

Ken Davis, Results for n!4+1.

Crossrefs

Cf. A007662 (quadruple factorials), A085147.

Sequence in context: A052930 A098853 A023149 * A066894 A233919 A111115

Adjacent sequences: A085143 A085144 A085145 * A085147 A085148 A085149

Keyword

hard,nonn

Author

Hugo Pfoertner, Jun 25 2003

Extensions

More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 03 2008

Status

approved