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A260680 Peaceable coexisting armies of queens: number of inequivalent configurations in A250000. 2
1, 1, 1, 8, 3, 34, 19, 70 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

Two solutions are regarded as equivalent if one can be obtained from the other by rotations, reflections, interchanging the colors (a group of order 16).

LINKS

Table of n, a(n) for n=1..8.

Luca Petrone, Graphic illustrations of a(6) and a(7)

EXAMPLE

For n = 3, a(3) = 1 because the following solution is unique:

-----

|W..|

|...|

|.B.|

-----

From Rob Pratt in A250000, Nov 30 2014 thru Jul 29 2015: (Start)

n=4:

------------------------------------------------

|..B.||.B..||.B..||....||.BB.||..B.||...W||..B.|

|....||.B..||...B||.B.B||....||.B..||.B..||...B|

|...B||....||....||....||....||...W||..B.||.W..|

|WW..||W.W.||W.W.||W.W.||W..W||W...||W...||W...|

------------------------------------------------

n=5:

---------------------

|W...W||..B.B||.W.W.|

|..B..||W....||..W..|

|.B.B.||..B.B||B...B|

|..B..||W....||..W..|

|W...W||.W.W.||B...B|

---------------------

(End)

CROSSREFS

Cf. A250000.

Sequence in context: A248294 A004734 A287645 * A182054 A302214 A049074

Adjacent sequences:  A260677 A260678 A260679 * A260681 A260682 A260683

KEYWORD

hard,nonn,more

AUTHOR

Christian Schroeder, Nov 15 2015

EXTENSIONS

a(6)-a(8) from Luca Petrone, Mar 11 2016

STATUS

approved

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Last modified November 15 16:49 EST 2018. Contains 317239 sequences. (Running on oeis4.)