A066081 a(n) = smallest m such that m+2^j and m-2^j are prime for all 0 < j <= n.

5, 9, 15, 50943795, 40874929095, 616517522595975, 93487500801880185, 64606701602327559675

Offset

1,1

Comments

Is this sequence infinite?

Links

Table of n, a(n) for n=1..8.

Felice Russo, Prime puzzle 167.

Marek Wolf, Conjectures on the gaps between consecutive primes

Example

9-4, 9-2, 9+2, 9+4 are prime, but not 5+4 = 7+2, therefore a(2) = 9.

Crossrefs

Prime quadruples: A014561, sextets: A061671, octets: A066082.

Sequence in context: A345953 A075133 A351826 * A076856 A242973 A315084

Adjacent sequences: A066078 A066079 A066080 * A066082 A066083 A066084

Keyword

hard,nonn

Author

Frank Ellermann, Dec 03 2001

Extensions

a(5) and a(6) from Don Reble, Dec 07 2001

a(7) from Jim Fougeron (Feb 07) confirmed by Phil Carmody, who also found a(8) (Feb 14 2002).

Status

approved