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Bisection of A025487
1

%I #8 Oct 31 2013 12:17:26

%S 1,4,8,16,30,36,60,72,120,144,192,216,256,360,420,480,576,768,864,960,

%T 1080,1260,1440,1680,1800,2048,2304,2520,2880,3360,3600,4096,4608,

%U 5040,5400,6144,6480,6912,7560,7776,8640,9240,10368,11520,12600,13440,13860

%N Bisection of A025487

%C A025487: least integer of each prime signature; also products of primorial numbers A002110. - _Robert G. Wilson v_, Dec 14 2005

%t PrimeExponents[n_] := Last /@ FactorInteger@n; lpe = {}; ln = {1}; Do[ pe = Sort@PrimeExponents@n; If[FreeQ[lpe, pe], AppendTo[lpe, pe]; AppendTo[ln, n]], {n, 15000}]; ln[[2# - 1]] & /@ Range@(Length@ln/2) (* _Robert G. Wilson v_ *)

%Y Cf. A099993.

%K nonn,easy

%O 1,2

%A _N. J. A. Sloane_, Nov 20 2004

%E More terms from _Robert G. Wilson v_, Dec 14 2005