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 A066359 Nonsquarefree numbers n such that phi(n) = phi(n-2)-phi(n-1), where phi is Euler's totient function. 0

%I

%S 46795,78183,112995,1986975,2411175,2689695,2744145,3619071,3712545,

%T 4738185,8184715,12176109,13342959,26400843,33789015,40425645,

%U 61114185,78464475,83333565,167077575,212066541,248682015,326834725,336828205,353707705,391078425,880254585

%N Nonsquarefree numbers n such that phi(n) = phi(n-2)-phi(n-1), where phi is Euler's totient function.

%C See comment in A066232.

%C Numbers in A066232 that are not squarefree.

%o (PARI) ph1=1; ph2=1; for(n=3, 880254585, ph3=eulerphi(n); if(issquarefree(n)==0, if(ph3==ph1-ph2, print1(n ", "))); ph1=ph2; ph2=ph3) /* _Donovan Johnson_, Oct 20 2012 */

%K nonn

%O 1,1

%A _Jason Earls_, Dec 20 2001

%E a(10)-a(27) from _Donovan Johnson_, Oct 20 2012

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Last modified November 29 13:17 EST 2021. Contains 349416 sequences. (Running on oeis4.)