

A147577


Numbers with exactly 4 distinct odd prime divisors {3,5,7,11}


7



1155, 3465, 5775, 8085, 10395, 12705, 17325, 24255, 28875, 31185, 38115, 40425, 51975, 56595, 63525, 72765, 86625, 88935, 93555, 114345, 121275, 139755, 144375, 155925, 169785, 190575, 202125, 218295, 259875, 266805, 280665, 282975, 317625
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OFFSET

1,1


COMMENTS

Successive numbers k such that EulerPhi[x]/x = m
( Family of sequences for successive n odd primes )
m=2/3 numbers with exactly 1 distinct prime divisor {3} see A000244
m=8/15 numbers with exactly 2 distinct prime divisors {3,5} see A033849
m=16/35 numbers with exactly 3 distinct prime divisors {3,5,7} see A147576
m=32/77 numbers with exactly 4 distinct prime divisors {3,5,7,11} see A147577
m=384/1001 numbers with exactly 5 distinct prime divisors {3,5,7,11,13} see A147578
m=6144/17017 numbers with exactly 6 distinct prime divisors {3,5,7,11,13,17} see A147579
m=3072/323323 numbers with exactly 7 distinct prime divisors {3,5,7,11,13,17,19} see A147580
m=110592/323323 numbers with exactly 8 distinct prime divisors {3,5,7,11,13,17,19,23} see A147581


LINKS

Table of n, a(n) for n=1..33.


MATHEMATICA

a = {}; Do[If[EulerPhi[x]/x == 32/77, AppendTo[a, x]], {x, 1, 1000000}]; a(*Artur Jasinski*)
Select[Range[350000], EulerPhi[#]/#==32/77&] (* Harvey P. Dale, Mar 25 2016 *)


CROSSREFS

A060735, A143207, A147571A147575, A147576A147580
Sequence in context: A309413 A046390 A234498 * A211133 A088012 A046406
Adjacent sequences: A147574 A147575 A147576 * A147578 A147579 A147580


KEYWORD

nonn


AUTHOR

Artur Jasinski, Nov 07 2008


STATUS

approved



