

A323624


The diagonal of the order of square grid cells touched by a circle expanding from the middle of a cell.


4



0, 2, 5, 10, 16, 22, 32, 40, 50, 62, 73, 88, 101, 118, 134, 152, 170, 189, 210, 230, 253, 275, 299, 325, 351, 381, 406, 435, 465, 495, 527, 561, 593, 628, 663, 699, 737, 775, 813, 853, 895, 935, 981, 1021, 1068, 1113, 1156, 1205, 1253, 1302, 1352, 1401, 1454, 1502, 1557, 1609, 1664, 1723
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OFFSET

0,2


COMMENTS

Related to, but not the same as the case with the circle centered at the corner of a cell, see A232499.


LINKS



PROG

(Python)
N = 12
from math import sqrt
# the distance to the edge of each cell
edges = [[1 for j in range(N)] for i in range(N)]
edges[0][0] = 0
for i in range(1, N):
edges[i][0] = i0.5
edges[0][i] = i0.5
for i in range(1, N):
for j in range(1, N):
edges[i][j] = sqrt((i0.5)**2+(j0.5)**2)
# the values of the distances
values = []
for i in range(N):
for j in range(N):
values.append(edges[i][j])
values = list(set(values))
values.sort()
# the cell order
board = [[1 for j in range(N)] for i in range(N)]
count = 0
for v in values:
for i in range(N):
for j in range(N):
if(edges[i][j] == v):
board[i][j] = count
count += 1
# print out the sequence
for i in range(N):
print(str(board[i][i])+", ", end="")


CROSSREFS

For the grid read by antidiagonals see A323621.
For the first row of the grid see A323622.
For the second row of the grid see A323623.
For the (2,1) diagonal of the grid see A323625.


KEYWORD

nonn


AUTHOR



STATUS

approved



