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A238581
Number T(n,k) of equivalence classes of ways of placing k 2 X 2 tiles in an n X 9 rectangle under all symmetry operations of the rectangle; irregular triangle T(n,k), n>=2, 0<=k<=4*floor(n/2), read by rows.
21
1, 4, 12, 10, 3, 1, 4, 24, 40, 22, 1, 8, 65, 230, 467, 476, 269, 70, 9, 1, 8, 109, 641, 2281, 4424, 4718, 2409, 473, 1, 12, 182, 1479, 7644, 24024, 47022, 56226, 41000, 17834, 4545, 625, 39, 1, 12, 258, 2762, 19347, 86536, 255552, 495547, 625705, 499314, 239254, 61732, 6533
OFFSET
2,2
LINKS
Christopher Hunt Gribble, C++ program
EXAMPLE
The first 4 rows of T(n,k) are:
.\ k 0 1 2 3 4 5 6 7 8
n
2 1 4 12 10 3
3 1 4 24 40 22
4 1 8 65 230 467 476 269 70 9
5 1 8 109 641 2281 4424 4718 2409 473
PROG
(C++) See Gribble link.
KEYWORD
tabf,nonn
AUTHOR
EXTENSIONS
Terms corrected and xrefs updated by Christopher Hunt Gribble, Apr 27 2015
Terms a(43) and beyond from Andrew Howroyd, May 29 2017
STATUS
approved