A319288 - OEIS

A319288

a(n) is the smallest k such that A319284(n, k) >= A319284(n, j) for all 0 <= j <= n.

0, 0, 1, 1, 2, 3, 4, 5, 5, 6, 7, 8, 9, 10, 11, 11, 12, 13, 14, 15

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OFFSET

0,5

COMMENTS

Intuitively this is the level in the backtrack tree of the n queens problem where the algorithm spends more time than on any other level.

The constraint 'is the smallest' in the name can be dropped if the profile of the backtrack tree of the n queens problem is unimodal (for n>1).

The corresponding maxima are: 1, 1, 2, 3, 6, 14, 46, 164, 568, 2292, 9632, 44148, 222720, 1151778, 6471872, 39290462, 260303408, 1812613348, 13308584992, 102670917500.

LINKS

Table of n, a(n) for n=0..19.

CROSSREFS

Cf. A319284, A000170.

Sequence in context: A228297 A303788 A366871 * A106744 A332613 A072932

Adjacent sequences: A319285 A319286 A319287 * A319289 A319290 A319291

KEYWORD

nonn,more

AUTHOR

Peter Luschny, Sep 16 2018

STATUS

approved