|
| |
|
|
A060666
|
|
Sigma(x) = n has exactly ten solutions.
|
|
0
|
|
|
|
504, 864, 960, 1152, 1260, 2400, 3276, 3888, 4992, 6696, 7020, 7644, 8892, 9672, 9984, 11172, 11200, 11376, 11616, 11856, 12936, 13728, 13888, 14136, 14280, 15480, 15876, 15984, 17808, 19488, 21336, 22608, 23688, 24738, 24840, 25080
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,1
|
|
|
LINKS
|
Table of n, a(n) for n=1..36.
|
|
|
EXAMPLE
|
504 = sigma(204) = sigma(220) = sigma(224) = sigma(246) = sigma(284) = sigma(286) = sigma(334) = sigma(415) = sigma(451) = sigma(504).
|
|
|
MATHEMATICA
|
a = Table[ 0, {30000} ]; Do[ s = DivisorSigma[ 1, n ]; If[ s < 30001, a[ [ s ] ]++ ], {n, 1, 30000} ]; Select[ Range[ 30000 ], a[ [ # ] ] == 10 & ]
|
|
|
CROSSREFS
|
Cf. A007370, A007371, A007372.
Sequence in context: A066525 A043304 A045212 * A161005 A180164 A061124
Adjacent sequences: A060663 A060664 A060665 * A060667 A060668 A060669
|
|
|
KEYWORD
|
nonn
|
|
|
AUTHOR
|
Robert G. Wilson v, Apr 18 2001
|
|
|
STATUS
|
approved
|
| |
|
|
