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A005108 Class 4+ primes.
(Formerly M5350)
24
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; refs; listen; history; internal format)
OFFSET

1,1

REFERENCES

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).

LINKS

T. D. Noe, Table of n, a(n) for n=1..10000

MAPLE

For Maple program see Mathar link.

MATHEMATICA

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 &]]

CROSSREFS

Cf. A005113, A005105, A005106, A005107.

Sequence in context: A142614 A158744 A142406 * A142810 A142279 A092342

Adjacent sequences:  A005105 A005106 A005107 * A005109 A005110 A005111

KEYWORD

nonn

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com), Simon Plouffe (simon.plouffe(AT)gmail.com)

EXTENSIONS

Edited and extended by Robert G. Wilson v (rgwv(AT)rgwv.com), Mar 20 2003

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Last modified February 16 16:00 EST 2012. Contains 205938 sequences.