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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A213952 Consider the partitions of n in reverse lexicographic ordering (A080577), a(n) is the position of the partition of n which has the maximum LCM. See A000793.

Original entry on oeis.org

1, 1, 1, 1, 3, 1, 5, 5, 8, 15, 13, 33, 49, 35, 49, 73, 107, 143, 211, 293, 398, 505, 510, 685, 710, 948, 740, 994, 2033, 1735, 2266, 1780, 2333, 4653, 5923, 7311, 9213, 7683, 9719, 17878, 14703, 19072, 22814, 28266, 34878, 42876, 52390
Offset: 1

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Author

Robert G. Wilson v, Jul 04 2012

Keywords

Comments

As n grows, a(n)/P(n) -> ~1/3, where P(n) is A000041(n).

Examples

			a(5) = 3 because of the seven partitions of 5, {{5}, {4, 1}, {3, 2}, {3, 1, 1}, {2, 2, 1}, {2, 1, 1, 1}, {1, 1, 1, 1, 1}}; the LCMs of each are: {5, 4, 6, 3, 2, 2, 1}. The third one is the maximum.
		

Crossrefs

Programs

  • Mathematica
    f[n_] := Block[{lst = Apply[LCM, IntegerPartitions@ n, 1]}, Flatten[ Position[ lst, Max@ lst, 1, 1], 1][[1]]]; Array[f, 47]