

A147579


Numbers with exactly 6 distinct odd prime divisors {3,5,7,11,13,17}


7



255255, 765765, 1276275, 1786785, 2297295, 2807805, 3318315, 3828825, 4339335, 5360355, 6381375, 6891885, 8423415, 8933925, 9954945, 11486475, 12507495, 13018005, 14039025, 16081065, 16591575, 19144125, 19654635, 20675655
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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..24.


MATHEMATICA

a = {}; Do[If[EulerPhi[255255 x] == 92160 x, AppendTo[a, 255255 x]], {x, 1, 100}]; a(*Artur Jasinski*)


CROSSREFS

A060735, A143207, A147571A147575, A147576A147580
Sequence in context: A140079 A034631 A168352 * A087025 A249915 A161534
Adjacent sequences: A147576 A147577 A147578 * A147580 A147581 A147582


KEYWORD

nonn


AUTHOR

Artur Jasinski, Nov 07 2008


STATUS

approved



