%I A005112 M5289
%S A005112 47,139,167,179,269,277,347,461,467,499,599,643,691,709,797,827,829,839,
%T A005112 857,863,967,997,1013,1019,1039,1063,1069,1151,1163,1181,1289,1367,1381,
%U A005112 1399,1427,1487,1493,1499,1579,1609,1619,1657,1867,1877,1889,1933,1979
%N A005112 Class 4- primes.
%D A005112 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, 
               Academic Press, 1995 (includes this sequence).
%D A005112 R. K. Guy, Unsolved Problems in Number Theory, A18.
%H A005112 R. J. Mathar, <a href="b005112.txt">Table of n, a(n) for n = 1..20000</
               a>
%t A005112 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]]; ClassMinusNbr[n_] := Length[NestWhileList[f, n, UnsameQ, All]] 
               - 3; Prime[ Select[ Range[300], ClassMinusNbr[ Prime[ # ]] == 4 &]]
%Y A005112 Cf. A005113, A056637, A005109, A005110, A005111, A081424, A081425, A081426, 
               A081427, A081428, A081429, A081430
%Y A005112 Sequence in context: A044679 A039530 A095311 this_sequence A062637 A040984 
               A136070
%Y A005112 Adjacent sequences: A005109 A005110 A005111 this_sequence A005113 A005114 
               A005115
%K A005112 nonn
%O A005112 1,1
%A A005112 N. J. A. Sloane (njas(AT)research.att.com), Simon Plouffe (simon.plouffe(AT)gmail.com)
%E A005112 Edited and extended by Robert G. Wilson v (rgwv(AT)rgwv.com), Mar 20 
               2003