|
| |
|
|
A018807
|
|
Number of ways to place n^2 nonattacking kings on 2n X 2n chessboard.
|
|
12
| |
|
|
4, 79, 3600, 281571, 32572756, 5109144543, 1027533353168, 254977173389319, 75925129079783308, 26568150968269086211, 10749154284380665611224, 4963704194366362387891227, 2588716234142991968960920692, 1511548995678989691821551648635
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,1
|
|
|
COMMENTS
| Rotations and reflections are considered distinct.
Also, number of ways to tile a (2n+1) x (2n+1) board with n^2 2x2 tiles and 4n+1 1x1 tiles, rotations and reflections counted as distinct. - David W. Wilson, Aug 18 2011
|
|
|
REFERENCES
| Michael Larsen, The Problem of Kings, The Electronic Journal of Combinatorics 2, 1995
|
|
|
LINKS
| Zealint Blog (russian) Source for a(12) through a(20), March 14 2011. a(21) through a(26) from same source, July 9 2011.
Michael Larsen, The Problem of Kings, The Electronic Journal of Combinatorics 2, 1995
David W. Wilson, Table of n, a(n) for n = 1..26
|
|
|
FORMULA
| Asymptotic (M. Larsen, 1995): log(a(n)) = 2n*log(n) - 2n*log(2) + O(n^(4/5)*log(n)).
|
|
|
CROSSREFS
| Cf. A174558, A174155, A174154, A173782, A173783, A061594, A061593.
Sequence in context: A048957 A006425 A065930 * A125710 A204296 A192790
Adjacent sequences: A018804 A018805 A018806 * A018808 A018809 A018810
|
|
|
KEYWORD
| nonn,nice
|
|
|
AUTHOR
| David W. Wilson (davidwwilson(AT)comcast.net)
|
| |
|
|
