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A positive integer n is included if n is the smallest integer in a run of a plural number of consecutive integers all with the same number of divisors.
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%I #9 Apr 09 2014 10:15:19

%S 2,14,21,26,33,38,44,57,75,85,93,98,104,116,118,122,133,135,141,145,

%T 147,158,171,177,189,201,205,213,217,230,242,253,285,296,298,301,326,

%U 332,334,344,374,381,387,393,429,434,445,453,481,501,507,514,526,537,542

%N A positive integer n is included if n is the smallest integer in a run of a plural number of consecutive integers all with the same number of divisors.

%C All terms of this sequence are included in sequence A005237.

%e d(33) = d(34) = d(35), where d(n) is the number of divisors of n. And since d(32) does not equal d(33), d(33) is the first term of this run of similar values. So 33 is included in this sequence.

%t (First /@ Select[ Split[ Table[ {DivisorSigma[0, n], n}, {n, 1, 600}], First[#1] == First[#2] &] , Length[#] > 1 &])[[All, 2]] (* _Jean-François Alcover_, Oct 07 2013 *)

%Y Cf. A005237.

%K nonn

%O 1,1

%A _Leroy Quet_, Jul 05 2008

%E Extended by _Ray Chandler_, Jun 25 2009