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A187431
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Numbers n that generate 5 primes under the first 5 iterations of the map n->A002731(n).
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6
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30131199, 50817201, 56496039, 74316929, 171407609, 276672151, 293315671, 337876949, 356498179, 359830101, 372590921, 432448789, 501182201, 541961069, 577016839, 616411051, 749536461, 776113741, 903321909, 919203811, 1005047121, 1285328811, 1323139751, 1340738371
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OFFSET
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1,1
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COMMENTS
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Numbers n such that m=(n^2+1)/2, p=(m^2+1)/2, q=(p^2+1)/2, r=(q^2+1)/2 and s=(r^2+1)/2 are all prime.
Two numbers n that generate 6 primes... are a(23)=1323139751 and a(78)=10185588801.
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LINKS
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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