That's mostly correct. My definition is that it is a set of lattice points, not cells, of the form D intersect Z^2, for some closed disk D. (Open disks give the same polyominoes, but require slightly more finicky reasoning.) On Thu, Apr 12, 2012 at 10:05 PM, David Wilson <davidwwilson@comcast.net>wrote:
I have kind of lazily been following this thread.
By "disk polyomino", do we mean a polyomino consisting of the grid cells lying entirely within some circular disk?
On 4/12/2012 4:43 PM, Allan Wechsler wrote:
And since *then*, I have found a[19]=a[20]=3, and then a[21]=5. This is
all very much not what I expected, and even more interesting than I thought it would be. I'm going to update OEIS, but then I think I'm going to stop for a while, because this is all being done by hand, and the farther I go the more chance there is of getting something wrong.
Still no well-defined algorithm.
2012/4/10 Allan Wechsler<acwacw@gmail.com>
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