A238586 Number T(n,k) of equivalence classes of ways of placing k 2 X 2 tiles in an n X 10 rectangle under all symmetry operations of the rectangle; irregular triangle T(n,k), n>=2, 0<=k<=5*floor(n/2), read by rows.

1, 5, 16, 19, 9, 1, 1, 5, 32, 73, 66, 10, 1, 10, 85, 377, 961, 1348, 1080, 472, 111, 12, 1, 1, 10, 142, 1011, 4429, 11370, 17252, 14478, 6094, 1020, 70, 1, 15, 236, 2280, 14203, 56571, 146212, 244063, 261847, 179063, 77974, 21422, 3637, 368, 24, 1

Offset

2,2

Links

Andrew Howroyd, Table of n, a(n) for n = 2..937

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     9    10
n
2    1     5    16    19     9     1
3    1     5    32    73    66    10
4    1    10    85   377   961  1348  1080   472   111    12     1
5    1    10   142  1011  4429 11370 17252 14478  6094  1020    70

Prog

(C++) See Gribble link.

Crossrefs

Cf. A034851, A226048, A102541, A226290, A238009, A228570, A225812, A238189, A238190, A228572, A228022, A231145, A231473, A231568, A232440, A228165, A238550-A238552, A228166, A238555, A238556, A228167, A238557-A238559, A228168, A238581-A238583, A228169, A238592.

Sequence in context: A227871 A298226 A298150 * A195958 A151980 A063612

Adjacent sequences: A238583 A238584 A238585 * A238587 A238588 A238589

Keyword

tabf,nonn

Author

Christopher Hunt Gribble, Mar 01 2014

Extensions

Terms corrected and crossrefs updated by Christopher Hunt Gribble, Apr 27 2015

Terms a(36) and beyond from Andrew Howroyd, May 29 2017

Status

approved