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A057325
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First member of a prime quadruple in a p^2+p-1 progression.
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1
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3, 11, 53, 1693, 2663, 4423, 16831, 17609, 36229, 49801, 94961, 121493, 150869, 176303, 183761, 188011, 210901, 213833, 218579, 272903, 300301, 329671, 439511, 444791, 453023, 469613, 518813, 531911, 546071, 559703, 570719, 614279, 705781
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,1
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COMMENTS
| I found only one prime quintuplet so far: (3,11,131,17291,298995971).
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LINKS
| Index entries for sequences related to primes in arithmetic progressions
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EXAMPLE
| 3 -> 3^2+3-1 = 11 -> 11^2+11-1 = 131 -> 131^2+131-1 = 17291 hence the quadruple (3,11,131,17291).
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MATHEMATICA
| okQ[n_] := And@@PrimeQ/@NestList[#^2 + # - 1 &, n, 3]
Select[Prime[Range[60000]], okQ] (* From Harvey P. Dale, Jan 05 2011 *)
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CROSSREFS
| Cf. A053184, A053185, A057324.
Sequence in context: A081367 A156171 A129093 * A054700 A009280 A095707
Adjacent sequences: A057322 A057323 A057324 * A057326 A057327 A057328
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KEYWORD
| nonn
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AUTHOR
| Patrick De Geest (pdg(AT)worldofnumbers.com), Aug 15 2000.
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