

A231145


Number T(n,k) of equivalence classes of ways of placing k 2 X 2 tiles in an n X 5 rectangle under all symmetry operations of the rectangle; irregular triangle T(n,k), n>=2, 0<=k<=nn%2, read by rows.


22



1, 2, 2, 1, 2, 4, 1, 4, 13, 10, 4, 1, 4, 23, 35, 23, 1, 6, 40, 101, 125, 54, 10, 1, 6, 58, 206, 403, 336, 106, 1, 8, 83, 392, 1056, 1438, 956, 240, 25, 1, 8, 109, 641, 2281, 4424, 4718, 2409, 473, 1, 10, 142, 1011, 4429, 11370, 17252, 14478, 6094, 1020, 70
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OFFSET

2,2


LINKS



EXAMPLE

The first 8 rows of T(n,k) are:
.\ k 0 1 2 3 4 5 6 7 8
n
2 1 2 2
3 1 2 4
4 1 4 13 10 4
5 1 4 23 35 23
6 1 6 40 101 125 54 10
7 1 6 58 206 403 336 106
8 1 8 83 392 1056 1438 956 240 25
9 1 8 109 641 2281 4424 4718 2409 473


PROG

(C++) See Gribble link.


CROSSREFS

Cf. A034851, A226048, A102541, A226290, A238009, A228570, A225812, A238189, A238190, A228572, A228022, A231473, A231568, A232440, A228165, A238550, A238551, A238552, A228166, A238555, A238556, A228167, A238557, A238558, A238559, A228168, A238581, A238582, A238583, A228169, A238586, A238592.


KEYWORD

tabf,nonn


AUTHOR



EXTENSIONS



STATUS

approved



