A243866 Table T(n,k), n>=1, k>=1, read by antidiagonals: T(n,k) = number of equivalence classes of ways of placing one 1 X 1 tile in an n X k rectangle under all symmetry operations of the rectangle.
1, 1, 1, 2, 1, 2, 2, 2, 2, 2, 3, 2, 4, 2, 3, 3, 3, 4, 4, 3, 3, 4, 3, 6, 4, 6, 3, 4, 4, 4, 6, 6, 6, 6, 4, 4, 5, 4, 8, 6, 9, 6, 8, 4, 5, 5, 5, 8, 8, 9, 9, 8, 8, 5, 5, 6, 5, 10, 8, 12, 9, 12, 8, 10, 5, 6, 6, 6, 10, 10, 12, 12, 12, 12, 10, 10, 6, 6, 7, 6, 12, 10, 15
Offset: 1
Examples
T(n,k) for 1<=n<=11 and 1<=k<=11 is: k 1 2 3 4 5 6 7 8 9 10 11 ... .n .1 1 1 2 2 3 3 4 4 5 5 6 .2 1 1 2 2 3 3 4 4 5 5 6 .3 2 2 4 4 6 6 8 8 10 10 12 .4 2 2 4 4 6 6 8 8 10 10 12 .5 3 3 6 6 9 9 12 12 15 15 18 .6 3 3 6 6 9 9 12 12 15 15 18 .7 4 4 8 8 12 12 16 16 20 20 24 .8 4 4 8 8 12 12 16 16 20 20 24 .9 5 5 10 10 15 15 20 20 25 25 30 10 5 5 10 10 15 15 20 20 25 25 30 11 6 6 12 12 18 18 24 24 30 30 36 ...
Links
- Christopher Hunt Gribble, Table of n, a(n) for n = 1..9870
Crossrefs
Programs
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Maple
b := proc (n,k); floor((1/2)*n+1/2)*floor((1/2)*k+1/2) end proc; seq(seq(b(n, k-n+1), n = 1 .. k), k = 1 .. 140);
Formula
Extensions
Terms corrected by Christopher Hunt Gribble, Mar 27 2015
Comments