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A129648
Largest order of a permutation of n elements with exactly 3 cycles. Also the largest LCM of a 3-partition of n.
8
0, 0, 1, 2, 3, 6, 6, 12, 15, 30, 21, 60, 35, 84, 105, 140, 84, 210, 165, 280, 315, 360, 385, 504, 495, 630, 693, 792, 819, 990, 1001, 1170, 1287, 1430, 1365, 1716, 1683, 2002, 2145, 2310, 2431, 2730, 2805, 3120, 3315, 3570, 3705, 4080, 4199, 4560, 4845, 5168
OFFSET
1,4
COMMENTS
a(n) is asymptotic to (n^3)/27.
EXAMPLE
a(9) = 15 because 9 = 5+3+1 and lcm(1,3,5) = 15 is maximal.
MATHEMATICA
Max[LCM @@@ Compositions[ #, 3]] & /@ Range[1, n]
CROSSREFS
Maximal LCM of k positive integers with sum n for k = 2..7: A129647 (k=2), this sequence (k=3), A129649 (k=4), A129650 (k=5), A355367 (k=6), A355403 (k=7).
Sequence in context: A131259 A346758 A143177 * A129649 A129650 A355367
KEYWORD
nonn
AUTHOR
Nickolas Reynolds (nickels(AT)gmail.com), Apr 25 2007
STATUS
approved