|
| |
|
|
A125856
|
|
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.
|
|
0
| | |
|
|
|
OFFSET
| 0,1
|
|
|
COMMENTS
| 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}.
|
|
|
REFERENCES
| Sierpinski, W. Elementary theory of numbers. Warszawa 1964 Monografie Matematyczne Vol. 42.
|
|
|
CROSSREFS
| Cf. A125855, A057015, A125779, A125780.
Sequence in context: A016518 A118202 A089331 * A057110 A073275 A030120
Adjacent sequences: A125853 A125854 A125855 * A125857 A125858 A125859
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Artur Jasinski (grafix(AT)csl.pl), Dec 12 2006
|
|
|
EXTENSIONS
| Edited by Don Reble (djr(AT)nk.ca), Dec 16 2006
One more term from Farideh Firoozbakht (mymontain(AT)yahoo.com), Jan 01 2007
|
| |
|
|
