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A066081
a(n) = smallest m such that m+2^j and m-2^j are prime for all 0 < j <= n.
4
5, 9, 15, 50943795, 40874929095, 616517522595975, 93487500801880185, 64606701602327559675
OFFSET
1,1
COMMENTS
Is this sequence infinite?
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
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