|
Search: id:A086222
|
|
|
| A086222 |
|
Card{ (x,y,z) | x<=y<=z and LCM(x,y,z)=n } where LCM(x,y,z) denote the least common multiple of (x,y,z). |
|
+0
3
|
|
| 1, 3, 3, 6, 3, 13, 3, 10, 6, 13, 3, 30, 3, 13, 13, 15, 3, 30, 3, 30, 13, 13, 3, 54, 6, 13, 10, 30, 3, 71, 3, 21, 13, 13, 13, 73, 3, 13, 13, 54, 3, 71, 3, 30, 30, 13, 3, 85, 6, 30, 13, 30, 3, 54, 13, 54, 13, 13, 3, 178, 3, 13, 30, 28, 13, 71, 3, 30, 13, 71, 3, 135, 3, 13, 30, 30, 13, 71, 3
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
COMMENT
|
A number of conjectures are possible, many of which should be easy to prove. Examples: (1) If n is a product of two primes then a(n)=13. (2) If n is a square of a prime then a(n)=6. - John W. Layman (layman(AT)math.vt.edu), Sep 01 2003
|
|
FORMULA
|
For a prime p, a(p) = 3.
a(n) = (A070919(n)+3*A048691(n)+2)/6. - Vladeta Jovovic (vladeta(AT)Eunet.yu), Dec 01 2004
|
|
CROSSREFS
|
Cf. A070919, A018892.
Cf. A086165.
Sequence in context: A058587 A112163 A120909 this_sequence A086492 A143305 A051472
Adjacent sequences: A086219 A086220 A086221 this_sequence A086223 A086224 A086225
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Yuval Dekel (dekelyuval(AT)hotmail.com), Aug 28 2003
|
|
EXTENSIONS
|
More terms from John W. Layman (layman(AT)math.vt.edu), Sep 01 2003
|
|
|
Search completed in 0.002 seconds
|
