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A215130 Odd squarefree n not divisible by 3 such that n/phi(n) > 2, where phi is Euler's totient function. 1

%I

%S 37182145,46881835,50115065,59814755,1078282205,1152646495,1375739365,

%T 1453336885,1524467945,1598832235,1734627895,1747560815,1759302545,

%U 1854257405,1922155235,1966279315,1970653685,2015918905,2054717665,2099812715,2154947795,2193746555

%N Odd squarefree n not divisible by 3 such that n/phi(n) > 2, where phi is Euler's totient function.

%C Terms in A091495 not divisible by 3.

%C The first 5000 terms are divisible by both 5 and 7. a(2276) = 112435426285 is the smallest term not divisible by 11. - _Donovan Johnson_, Nov 03 2013

%H Donovan Johnson, <a href="/A215130/b215130.txt">Table of n, a(n) for n = 1..5000</a>

%o (PARI) forstep(n=1, 2193746557, [4,2], if(issquarefree(n), if(n/eulerphi(n)>2, print1(n ", "))))

%Y Cf. A091495, A000010.

%K nonn

%O 1,1

%A _Donovan Johnson_, Aug 04 2012

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Last modified February 7 16:06 EST 2023. Contains 360128 sequences. (Running on oeis4.)