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A066081
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a(n) = smallest m such that m+2^j and m-2^j are prime for all 0 < j <= n.
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4
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OFFSET
| 1,1
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COMMENTS
| Is this sequence infinite?
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LINKS
| Felice Russo, Prime puzzle 167.
Marek Wolf, Conjectures on the gaps between consecutive primes (gzipped postscript).
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EXAMPLE
| 9-4, 9-2, 9+2, 9+4 are prime, but not 5+4 = 7+2, therefore a(2) = 9.
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CROSSREFS
| Prime quadruples: A014561, sextets: A061671, octets: A066082.
Sequence in context: A023498 A062516 A075133 * A076856 A099541 A165594
Adjacent sequences: A066078 A066079 A066080 * A066082 A066083 A066084
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KEYWORD
| hard,nonn
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AUTHOR
| Frank Ellermann (hmdmhdfmhdjmzdtjmzdtzktdkztdjz(AT)gmail.com), Dec 03 2001
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EXTENSIONS
| a(5) and a(6) from Don Reble (djr(AT)nk.ca), Dec 07 2001
a(7) from Jim Fougeron (Feb 07) confirmed by Phil Carmody, who also found a(8) (Feb 14 2002).
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