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A051283 Numbers n such that if one writes n = Product p_i^e_i (p_i primes) and P = max p_i^e_i, then n/P > P. 4
30, 60, 70, 84, 90, 105, 120, 126, 132, 140, 154, 165, 168, 180, 182, 195, 198, 210, 220, 231, 234, 252, 260, 264, 273, 280, 286, 306, 308, 312, 315, 330, 336, 340, 357, 360, 364, 374, 380, 385, 390, 396, 399, 408, 418, 420, 429, 440, 442, 455, 456, 462 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A080170(n+1) + 1 (conjectured). - Ralf Stephan, Feb 20 2004

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

EXAMPLE

120 = 2^3*3^1*5^1, P = 2^3 = 8. 120 is included because 120/8 = 15 > 8.

MATHEMATICA

ok[n_] := n > Max[Power @@@ FactorInteger[n]]^2; Select[Range[465], ok] (* Jean-Fran├žois Alcover, Apr 11 2011 *)

PROG

(Haskell)

a051283 n = a051283_list !! (n-1)

a051283_list = filter (\x -> (a034699 x) ^ 2 < x) [1..]

-- Reinhard Zumkeller, May 30 2013

CROSSREFS

Cf. A034699.

Sequence in context: A051488 A305613 A267967 * A066031 A212666 A291046

Adjacent sequences:  A051280 A051281 A051282 * A051284 A051285 A051286

KEYWORD

nonn,easy,nice

AUTHOR

Leroy Quet

EXTENSIONS

More terms from James A. Sellers, Dec 11 1999

STATUS

approved

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Last modified October 23 18:27 EDT 2018. Contains 316529 sequences. (Running on oeis4.)