OFFSET

1,2

COMMENTS

See A341327 for the list of the spiral numbers not covered by any square in the tiling.

LINKS

Scott R. Shannon, Image of the first 60 squares. The image can be zoomed in to see the numbers of the square spiral. The colors are graduated across the spectrum to show the squares relative size/placement order.

EXAMPLE

The square spiral used is:

.

17--16--15--14--13 .

| | .

18 5---4---3 12 29

| | | | |

19 6 1---2 11 28

| | | |

20 7---8---9--10 27

| |

21--22--23--24--25--26

.

a(1) = 1 as a square of size 1 x 1 is placed on the number 1, which is the minimum possible value.

a(2) = 28 as a square of size 2 x 2 is placed such that it covers the numbers 2,3,11,12 which sum to 28. This is the minimum possible sum for such a square which does not use the previously covered number 1.

a(3) = 180 as a square of size 3 x 3 is placed such that it covers numbers 4,5,18,15,16,17,34,35,36 which sum to 180. This is the minimum possible sum for such a square which does not use the previously covered numbers 1,2,3,11,12.

CROSSREFS

KEYWORD

nonn

AUTHOR

Scott R. Shannon, Feb 06 2021

STATUS

approved