

A122465


Smooth Power Quartets: The mth number in the sequence, n, is part of the minimum quartet of numbers n through n3 such that the highest prime factor of each number x <= floor(x^(1/m)).


2




OFFSET

1,1


COMMENTS

These were found by R. Gerbicz.


LINKS

Table of n, a(n) for n=1..4.
Fred Schneider and R. Gerbicz, Smooth Power Trios.


EXAMPLE

1680 = 2^4*3*5*7, 1681 = 41^2, 1682 = 2*29^2, 1683 = 3^2*11*17; 7 < floor(sqrt(1680)) = 40 and 41 <= floor(sqrt(1681)) = 41, so 1683 is a term.


CROSSREFS

Cf. A122463, A122464.
Sequence in context: A237914 A057199 A198246 * A203683 A330057 A324265
Adjacent sequences: A122462 A122463 A122464 * A122466 A122467 A122468


KEYWORD

hard,more,nonn,uned


AUTHOR

Fred Schneider, Sep 09 2006


STATUS

approved



