A084404 Numbers n such that n#*2^n+1 is prime, where n# = product of primes <= n.

1, 4, 7, 20, 22, 27, 32, 37, 48, 68, 122, 128, 148, 152, 155, 159, 160, 198, 216, 217, 239, 247, 248, 306, 363, 429, 475, 515, 606, 651, 823, 1491, 1774, 1923, 2153, 2469, 2838, 2891, 2944, 3015, 3032, 3242, 3594, 4896, 5458, 5491, 5913, 6030

Offset

1,2

Comments

The values 1491 through 6030 have been proved prime; 6030#*2^6030+1 has 4386 decimal digits.

Links

Table of n, a(n) for n=1..48.

OpenPFGW Project, Primality Tester.

Crossrefs

Cf. A034386.

Sequence in context: A045548 A359733 A090879 * A147065 A049947 A266822

Adjacent sequences: A084401 A084402 A084403 * A084405 A084406 A084407

Keyword

nonn

Author

Jason Earls, Jun 24 2003

Status

approved