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A090778 phi(n) divides n*(n-phi(n)). 0
1, 2, 4, 6, 8, 10, 12, 16, 18, 20, 24, 32, 36, 40, 42, 48, 50, 54, 60, 64, 72, 80, 84, 96, 100, 108, 114, 120, 126, 128, 136, 144, 156, 160, 162, 168, 180, 192, 200, 216, 220, 228, 240, 250, 252, 256, 272, 288, 294, 300, 312, 320, 324, 336, 342, 360, 378, 384, 400 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

a(n) is also phi(n) divides n^2 [From Enrique Perez Herrero (psychgeometry(AT)gmail.com), Jul 04 2010]

FORMULA

a(n) seems to be asymptotic to c*n^2 with c=0.11.....

CROSSREFS

Sequence in context: A177917 A071594 A071596 * A097380 A114270 A109884

Adjacent sequences:  A090775 A090776 A090777 * A090779 A090780 A090781

KEYWORD

nonn

AUTHOR

Benoit Cloitre (benoit7848c(AT)orange.fr), Feb 08 2004

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Last modified February 17 04:58 EST 2012. Contains 205985 sequences.