cp's OEIS Frontend

A195088 Numbers k such that (number of prime factors of k counted with multiplicity) less (number of distinct prime factors of k) = 4.

%I A195088 #34 Sep 25 2024 10:28:34
%S A195088 32,96,144,160,216,224,243,324,352,400,416,480,486,544,608,672,720,
%T A195088 736,784,928,992,1000,1008,1056,1080,1120,1184,1200,1215,1248,1312,
%U A195088 1376,1504,1512,1584,1620,1632,1696,1701,1760,1800,1824,1872,1888,1936,1952
%N A195088 Numbers k such that (number of prime factors of k counted with multiplicity) less (number of distinct prime factors of k) = 4.
%C A195088 The asymptotic density of this sequence is (6/Pi^2) * Sum_{k>=1} f(a(k)) = 0.0237194..., where f(k) = A112526(k) * Product_{p|k} p/(p+1). - _Amiram Eldar_, Sep 24 2024
%H A195088 Reinhard Zumkeller, <a href="/A195088/b195088.txt">Table of n, a(n) for n = 1..10000</a>
%H A195088 <a href="/index/Eu#epf">Index entries for sequences computed from exponents in factorization of n</a>.
%F A195088 A046660(a(n)) = 4. - _Reinhard Zumkeller_, Nov 29 2015
%t A195088 Select[Range[2000],PrimeOmega[#]-PrimeNu[#]==4&]
%o A195088 (PARI) is(n)=bigomega(n)-omega(n)==4 \\ _Charles R Greathouse IV_, Sep 14 2015
%o A195088 (Haskell)
%o A195088 a195088 n = a195088_list !! (n-1)
%o A195088 a195088_list = filter ((== 4) . a046660) [1..]
%o A195088 -- _Reinhard Zumkeller_, Nov 29 2015
%Y A195088 Cf. A060687, A195069, A195086, A195087, A195089, A195090, A195091, A195092, A195093.
%Y A195088 Cf. A025487, A046660, A059956, A112526, A257851, A261256, A264959.
%K A195088 nonn,easy
%O A195088 1,1
%A A195088 _Harvey P. Dale_, Sep 08 2011