A093466 - OEIS

A093466

Triangle read by rows: T[n,k] = number of n X n binary matrices with k=0...n^2 ones, distinct up to cyclic shifts of rows and columns; reflection through any vertical or horizontal axis; and reflection through the main diagonal. Also, quasi-n-ominoes on a torus divided into a k X k grid.

1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 4, 5, 5, 4, 2, 1, 1, 1, 1, 5, 10, 33, 53, 101, 122, 153, 122, 101, 53, 33, 10, 5, 1, 1, 1, 1, 5, 19, 88, 309, 975, 2537, 5637, 10510, 16740, 22734, 26500, 26500, 22734, 16740, 10510, 5637, 2537, 975, 309, 88, 19, 5, 1, 1

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,5

LINKS

Table of n, a(n) for n=1..60.

EXAMPLE

[1,1], [1,1,2,1,1], [1,1,2,4,5,5,4,2,1,1] (the last block giving the numbers of 3 X 3 binary matrices with k=0...9 ones, distinct up to the transformations listed above.

CROSSREFS

Binary matrices with distinct rows and columns, various versions: A059202, A088309, A088310, A088616, A089673, A089674, A093466, A094000, A094223, A116532, A116539, A181230, A259763

Sequence in context: A242784 A265313 A106498 * A257463 A293483 A125761

Adjacent sequences: A093463 A093464 A093465 * A093467 A093468 A093469

KEYWORD

nonn,tabf

AUTHOR

Jon Wild, May 21, 2004

STATUS

approved