|
Search: id:A066694
|
|
|
| A066694 |
|
Numbers n such that EulerPhi(sigma(n)) > n. |
|
+0
1
|
|
| 4, 9, 16, 18, 25, 32, 36, 48, 50, 64, 72, 81, 84, 98, 100, 112, 144, 156, 162, 192, 196, 200, 225, 252, 256, 288, 289, 300, 324, 336, 338, 372, 392, 400, 432, 448, 450, 468, 484, 512, 576, 578, 624, 625, 648, 676, 700, 722, 729, 756, 768, 784, 800, 882, 900
(list; graph; listen)
|
|
|
OFFSET
|
1,1
|
|
|
FORMULA
|
It seems that a(n) is asymptotic to C*n*Log(n)^2 with C=1.38.... - Benoit Cloitre (benoit7848c(AT)orange.fr), Aug 07 2002
|
|
MATHEMATICA
|
Select[Range[1, 10^3], EulerPhi[DivisorSigma[1, # ]] > # &]
|
|
CROSSREFS
|
Adjacent sequences: A066691 A066692 A066693 this_sequence A066695 A066696 A066697
Sequence in context: A066925 A122379 A104020 this_sequence A102646 A104021 A073804
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
Joseph L. Pe (joseph_l_pe(AT)hotmail.com), Jan 09 2002
|
|
EXTENSIONS
|
More terms from Benoit Cloitre (benoit7848c(AT)orange.fr), Jul 31 2002
|
|
|
Search completed in 0.002 seconds
|
