|
| |
|
|
A072750
|
|
Counting factor 7 in squarefree numbers <=n.
|
|
4
| |
|
|
0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 12
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,10
|
|
|
EXAMPLE
| The first 10 squarefree numbers are: 1, 2, 3, 5, 6=2*3, 7, 10=2*5, 11, 13 and 14=2*7
7 and 14 are divisible by 7, therefore a(10)=2.
|
|
|
CROSSREFS
| Cf. A005117, A072747, A072748, A072749, A072751.
Sequence in context: A052375 A171626 A074279 * A186437 A029835 A074280
Adjacent sequences: A072747 A072748 A072749 * A072751 A072752 A072753
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Jul 08 2002
|
| |
|
|
