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Search: id:A005108
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| A005108 |
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Class 4+ primes.
(Formerly M5350)
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+0
24
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| 73, 313, 443, 617, 661, 673, 677, 691, 739, 757, 823, 887, 907, 941, 977, 1093, 1109, 1129, 1201, 1213, 1303, 1361, 1447, 1453, 1543, 1553, 1621, 1627, 1657, 1753, 1811, 1867, 1873, 1993, 1997, 2017, 2081, 2083, 2113, 2269, 2273, 2281, 2293, 2333, 2341
(list; graph; listen)
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OFFSET
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1,1
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REFERENCES
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R. K. Guy, Unsolved Problems in Number Theory, A18.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
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MAPLE
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For Maple program see Mathar link.
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MATHEMATICA
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PrimeFactors[n_Integer] := Flatten[ Table[ #[[1]], {1}] & /@ FactorInteger[n]]; f[n_Integer] := Block[{m = n}, If[m == 0, m = 1, While[ IntegerQ[m/2], m /= 2]; While[ IntegerQ[m/3], m /= 3]]; Apply[Times, PrimeFactors[m] + 1]]; ClassPlusNbr[n_] := Length[ NestWhileList[f, n, UnsameQ, All]] - 3; Prime[ Select[ Range[350], ClassPlusNbr[ Prime[ # ]] == 4 &]]
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CROSSREFS
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Cf. A005113, A005105, A005106, A005107.
Sequence in context: A142614 A158744 A142406 this_sequence A142810 A142279 A092342
Adjacent sequences: A005105 A005106 A005107 this_sequence A005109 A005110 A005111
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KEYWORD
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nonn
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AUTHOR
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N. J. A. Sloane (njas(AT)research.att.com), Simon Plouffe (simon.plouffe(AT)gmail.com)
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EXTENSIONS
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Edited and extended by Robert G. Wilson v (rgwv(AT)rgwv.com), Mar 20 2003
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