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A157468
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Primes of the form sqrt(p-1)-1, where p is a prime.
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1
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3, 5, 13, 19, 23, 53, 73, 83, 89, 109, 149, 179, 223, 229, 239, 263, 269, 283, 313, 349, 383, 419, 439, 443, 463, 569, 593, 643, 653, 673, 739, 859, 863, 919, 929, 1009, 1069, 1093, 1123, 1289, 1319, 1373, 1409, 1429, 1433, 1439, 1459
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| Let sqrt(p-1)-1=q. Then q^2+2q+2 = p. [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Apr 10 2010]
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EXAMPLE
| Sqrt[17-1]-1=3(prime), Sqrt[37-1]-1=5(prime), ...
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MATHEMATICA
| lst={}; Do[p=Prime[n]; r=Sqrt[p-1]-1; If[PrimeQ[r], AppendTo[lst, r]], {n, 4*8!}]; lst
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CROSSREFS
| Cf. A127435, A127436, A157467
Sequence in context: A045413 A108702 A136053 * A191017 A157974 A019420
Adjacent sequences: A157465 A157466 A157467 * A157469 A157470 A157471
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KEYWORD
| nonn
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AUTHOR
| Vladimir Orlovsky (4vladimir(AT)gmail.com), Mar 01 2009
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