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A147575 Numbers with exactly 8 distinct prime divisors {2,3,5,7,11,13,17,19}.

%I A147575 #13 Nov 12 2020 10:35:10
%S A147575 9699690,19399380,29099070,38798760,48498450,58198140,67897830,
%T A147575 77597520,87297210,96996900,106696590,116396280,126095970,135795660,
%U A147575 145495350,155195040,164894730,174594420,184294110,193993800,203693490,213393180,232792560,242492250,252191940
%N A147575 Numbers with exactly 8 distinct prime divisors {2,3,5,7,11,13,17,19}.
%C A147575 Successive numbers k such that EulerPhi(x)/x = m:
%C A147575 ( Family of sequences for successive n primes )
%C A147575 m=1/2 numbers with exactly 1 distinct prime divisor {2} see A000079
%C A147575 m=1/3 numbers with exactly 2 distinct prime divisors {2,3} see A033845
%C A147575 m=4/15 numbers with exactly 3 distinct prime divisors {2,3,5} see A143207
%C A147575 m=8/35 numbers with exactly 4 distinct prime divisors {2,3,5,7} see A147571
%C A147575 m=16/77 numbers with exactly 5 distinct prime divisors {2,3,5,7,11} see A147572
%C A147575 m=192/1001 numbers with exactly 6 distinct prime divisors {2,3,5,7,11,13} see A147573
%C A147575 m=3072/17017 numbers with exactly 7 distinct prime divisors {2,3,5,7,11,13,17} see A147574
%C A147575 m=55296/323323 numbers with exactly 8 distinct prime divisors {2,3,5,7,11,13,17,19} see A147575
%H A147575 Amiram Eldar, <a href="/A147575/b147575.txt">Table of n, a(n) for n = 1..10000</a>
%F A147575 a(n) = 9699690 * A080682(n). - _Amiram Eldar_, Mar 10 2020
%F A147575 Sum_{n>=1} 1/a(n) = 1/1658880. - _Amiram Eldar_, Nov 12 2020
%t A147575 a = {}; Do[If[EulerPhi[9699690 x] == 1658880 x, AppendTo[a, 9699690 x]], {x, 1, 100}]; a
%Y A147575 Cf. A060735, A080682, A143207, A147571-A147575, A147576-A147580.
%K A147575 nonn
%O A147575 1,1
%A A147575 _Artur Jasinski_, Nov 07 2008
%E A147575 More terms from _Amiram Eldar_, Mar 10 2020