login
A092980
Partition the sequence of natural numbers into groups so that each group product is just >=n! until the group contains only one number which is >= n!; a(n) = the number of such groups.
2
1, 2, 3, 12, 58, 355, 2507, 20123, 181332, 1814067, 19957313, 239497077, 3113497076, 43589095986, 653836992433, 10461394179218, 177843710898562, 3201186839512209, 60822550146244234, 1216451003828243036
OFFSET
1,2
COMMENTS
The largest member of the second group is given by A092979(n).
EXAMPLE
For n = 3 the groups are (1,2,3), (4,5), (6) so a(3)= 3.
For n = 4 the groups are (1,2,3,4),(5,6),(7,8),(9,10),(11,12),(13,14),(15,16),(17,18),(19,20),(21,22),(23,24),(25), so a(4) = 12.
For n = 7 the groups are (1,2,3,4,5,6,7), (8,9,10,11), (12,13,14,15),(16,17,18,19),(20,21,22),(23,24,25),(26,27,28),... so a(7)= 2507.
CROSSREFS
Cf. A092979.
The largest member of the second group is given by A092979(n).
Sequence in context: A025231 A366454 A094532 * A191464 A052183 A123899
KEYWORD
nonn
AUTHOR
Bobby L. Wilson (bwilson4(AT)radar.gsw.edu), following a suggestion of Amarnath Murthy, Jun 05 2004
EXTENSIONS
More terms from John W. Layman, Nov 18 2004
Further terms from William Rex Marshall, Jun 22 2005
STATUS
approved