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A099992 Bisection of A025487 1
1, 4, 8, 16, 30, 36, 60, 72, 120, 144, 192, 216, 256, 360, 420, 480, 576, 768, 864, 960, 1080, 1260, 1440, 1680, 1800, 2048, 2304, 2520, 2880, 3360, 3600, 4096, 4608, 5040, 5400, 6144, 6480, 6912, 7560, 7776, 8640, 9240, 10368, 11520, 12600, 13440, 13860 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

A025487: least integer of each prime signature; also products of primorial numbers A002110. - Robert G. Wilson v, Dec 14 2005

LINKS

Table of n, a(n) for n=1..47.

MATHEMATICA

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 *)

CROSSREFS

Cf. A099993.

Sequence in context: A302508 A030119 A034451 * A301149 A301143 A215349

Adjacent sequences:  A099989 A099990 A099991 * A099993 A099994 A099995

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, Nov 20 2004

EXTENSIONS

More terms from Robert G. Wilson v, Dec 14 2005

STATUS

approved

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Last modified March 20 19:23 EDT 2019. Contains 321349 sequences. (Running on oeis4.)