|
| |
|
|
A060301
|
|
For n>3: a(n) is a multiple of three distinct earlier terms.
|
|
0
| |
|
|
2, 3, 5, 30, 180, 300, 450, 1080, 1800, 2700, 3000, 4500, 6480, 6750, 10800, 16200, 18000, 27000, 30000, 38880, 40500, 45000, 64800, 67500, 97200, 101250, 108000, 162000, 180000, 233280, 243000, 270000, 300000, 388800, 405000, 450000, 583200
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,1
|
|
|
FORMULA
| a(n) is of the form 2^b*3^c*5^d where either b+c+d=1, or where each of b, c and d are positive and the largest of the three is an odd number less than the sum of the other two. For n>3: a(n) is 30 times a power of 6 times a power of 10 times a power of 15.
|
|
|
EXAMPLE
| a(15)=10800=2*30*180=a(1)*a(4)*a(5)
|
|
|
CROSSREFS
| Cf. A000423.
Sequence in context: A110389 A083388 A090475 * A040119 A186635 A106308
Adjacent sequences: A060298 A060299 A060300 * A060302 A060303 A060304
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Henry Bottomley (se16(AT)btinternet.com), Mar 28 2001
|
| |
|
|
