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%I #6 Mar 27 2015 21:32:53
%S 90,126,180,252,270,350,360,378,504,525,540,550,594,630,650,700,702,
%T 756,810,825,850,918,950,975,1026,1050,1078,1080,1100,1134,1150,1188,
%U 1242,1260,1274,1275,1300,1350,1400,1404,1425,1512,1575,1617,1620,1650,1666,1700,1725,1750,1782,1836,1862,1890,1900,1911,1950
%N Numbers divisible by at least three distinct primes whose largest prime power factor is not based on its smallest nor its greatest prime factor.
%C This sequence contains all unimodal composites (numbers whose list of prime factors is strictly increasing then strictly decreasing).
%e 90 is the first member of this sequence because its prime factor decomposition is 2*3^2*5, using the three smallest primes and 3^2 = 9 is the first power of 3 greater than 5 (and 2).
%t Module[{pfl},
%t Select[Range[2000],
%t Function[n, pfl = Power @@@ FactorInteger[n];
%t 1 < First[First[Position[pfl, Max[pfl], 1]]] < Length[pfl]]]]
%Y Cf. A057715 (numbers with strictly decreasing prime power factor list).
%K nonn,easy
%O 1,1
%A _Olivier Gérard_, Dec 30 2014
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