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Search: id:A162574
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| A162574 |
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Primes of the form 2^x+x+y+2^y, with x and y integers of any sign. |
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+0
4
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| 2, 7, 17, 23, 31, 43, 71, 73, 107, 541, 2129, 4111, 4243, 9239, 18457, 32789, 32803, 65563, 65687, 73757, 135197, 147487, 264221, 589859, 786469, 1048633, 1049117, 4194329, 4194847, 4227109, 8388637, 8392739, 8405029, 8650793, 16908329
(list; graph; listen)
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OFFSET
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1,1
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EXAMPLE
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a(1) = A006127(1)+A006127(1) =2. a(2) = a006127(1)+A006127(3)=7.
a(3) = A006127(4)+A006127(3) =17. a(4) = a006127(5)+A006127(2) = 23.
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MATHEMATICA
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f[x_, y_]:=2^x+x+y+2^y; lst={}; Do[Do[p=f[x, y]; If[PrimeQ[p], AppendTo[lst, p]], {y, -5!, 6!}], {x, -5!, 6!}]; Take[Union[lst], 5! ]
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CROSSREFS
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Cf. A162573, A006127.
Sequence in context: A049558 A049546 A049578 this_sequence A049542 A049582 A031377
Adjacent sequences: A162571 A162572 A162573 this_sequence A162575 A162576 A162577
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KEYWORD
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nonn
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AUTHOR
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Vladimir Orlovsky (4vladimir(AT)gmail.com), Jul 06 2009
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EXTENSIONS
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Examples added by R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Sep 17 2009
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