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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
46795, 78183, 112995, 1986975, 2411175, 2689695, 2744145, 3619071, 3712545, 4738185, 8184715, 12176109, 13342959, 26400843, 33789015, 40425645, 61114185, 78464475, 83333565, 167077575, 212066541, 248682015, 326834725, 336828205, 353707705, 391078425, 880254585 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

See comment in A066232.

Numbers in A066232 that are not squarefree.

LINKS

Table of n, a(n) for n=1..27.

PROG

(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 */

CROSSREFS

Sequence in context: A205474 A232411 A171103 * A234774 A236053 A109030

Adjacent sequences:  A066356 A066357 A066358 * A066360 A066361 A066362

KEYWORD

nonn

AUTHOR

Jason Earls, Dec 20 2001

EXTENSIONS

a(10)-a(27) from Donovan Johnson, Oct 20 2012

STATUS

approved

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Last modified October 18 01:39 EDT 2021. Contains 348065 sequences. (Running on oeis4.)