%I #12 Dec 22 2020 02:14:01
%S 111546435,334639305,557732175,780825045,1003917915,1227010785,
%T 1450103655,1673196525,1896289395,2119382265,2342475135,2565568005,
%U 2788660875,3011753745,3681032355,3904125225,4350310965,5019589575,5465775315,5688868185,6135053925,6358146795
%N Numbers with exactly 8 distinct odd prime divisors {3,5,7,11,13,17,19,23}.
%C Numbers k such that phi(k)/k = m
%C ( Family of sequences for successive n odd primes )
%C m=2/3 numbers with exactly 1 distinct prime divisor {3} see A000244
%C m=8/15 numbers with exactly 2 distinct prime divisors {3,5} see A033849
%C m=16/35 numbers with exactly 3 distinct prime divisors {3,5,7} see A147576
%C m=32/77 numbers with exactly 4 distinct prime divisors {3,5,7,11} see A147577
%C m=384/1001 numbers with exactly 5 distinct prime divisors {3,5,7,11,13} see A147578
%C m=6144/17017 numbers with exactly 6 distinct prime divisors {3,5,7,11,13,17} see A147579
%C m=3072/323323 numbers with exactly 7 distinct prime divisors {3,5,7,11,13,17,19} see A147580
%C m=110592/323323 numbers with exactly 8 distinct prime divisors {3,5,7,11,13,17,19,23} see A147581
%H Amiram Eldar, <a href="/A147581/b147581.txt">Table of n, a(n) for n = 1..10000</a>
%F Sum_{n>=1} 1/a(n) = 1/36495360. - _Amiram Eldar_, Dec 22 2020
%t a = {}; Do[If[EulerPhi[111546435 x] == 36495360 x, AppendTo[a, 111546435 x]], {x, 1, 100}]; a
%Y Cf. A060735, A143207, A147571-A147575, A147576-A147580.
%K nonn
%O 1,1
%A _Artur Jasinski_, Nov 07 2008
%E More terms from _Amiram Eldar_, Mar 11 2020
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