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Search: id:A125856
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| A125856 |
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a(n) = least number k such that k^(2^n)+1, k^(2^n)+3, k^(2^n)+7 and k^(2^n)+9 are all prime. |
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+0 1
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OFFSET
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0,1
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COMMENT
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In 1958, Schinzel showed that for each n>0, there are infinitely many primes among the numbers k^(2^n)+{1,3,7, or 9}.
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REFERENCES
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Sierpinski, W. Elementary theory of numbers. Warszawa 1964 Monografie Matematyczne Vol. 42.
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CROSSREFS
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Cf. A125855, A057015, A125779, A125780.
Sequence in context: A016518 A118202 A089331 this_sequence A057110 A073275 A030120
Adjacent sequences: A125853 A125854 A125855 this_sequence A125857 A125858 A125859
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KEYWORD
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nonn
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AUTHOR
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Artur Jasinski (grafix(AT)csl.pl), Dec 12 2006
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EXTENSIONS
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Edited by Don Reble (djr(AT)nk.ca), Dec 16 2006
One more term from Farideh Firoozbakht (mymontain(AT)yahoo.com), Jan 01 2007
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