%I A006049
%S A006049 2,3,4,7,8,14,16,20,21,31,33,34,35,38,39,44,45,50,51,54,55,56,57,62,68,
%T A006049 74,75,76,85,86,87,91,92,93,94,95,98,99,111,115,116,117,118,122,123,127,
%U A006049 133,134,135,141,142,143,144,145,146,147,152,158,159,160,161,171,175
%N A006049 Numbers n such that n and n+1 have same number of distinct prime divisors.
%D A006049 C. Clawson, Mathematical mysteries, Plenum Press 1996, p. 250.
%H A006049 T. D. Noe, <a href="b006049.txt">Table of n, a(n) for n=1..2500</a>
%t A006049 f[n_] := Length@FactorInteger[n];t = f /@ Range[175];Flatten@Position[Rest[t]
- Most[t], 0] (*Chandler*)
%Y A006049 Cf. A001221, A052215, A107800.
%Y A006049 Sequence in context: A051213 A066847 A057887 this_sequence A084541 A113050
A097110
%Y A006049 Adjacent sequences: A006046 A006047 A006048 this_sequence A006050 A006051
A006052
%K A006049 nonn,easy,nice
%O A006049 1,1
%A A006049 N. J. A. Sloane (njas(AT)research.att.com).
%E A006049 Extended by Ray Chandler (rayjchandler(AT)sbcglobal.net), Mar 27 2007
|