OFFSET
1,3
COMMENTS
Points are not lying on the borders of the circle and the square.
Note that if the square is rotated so that its sides are parallel to the coordinate axes, the resulting sequence is A303642 instead.
LINKS
Kirill Ustyantsev, Desmos graph calculator
FORMULA
PROG
(Python)
for n in range (1, 100):
count=0
for x in range (0, n):
for y in range (0, n):
if (x*x+y*y<n*n and x+y>n):
count=count+1
print(4*count)
(PARI) a(n) = sum(x=-n, +n, sum(y=-n, +n, ((x^2+y^2) < n^2) && ((abs(x)+abs(y))^2 > n^2))); \\ Michel Marcus, May 22 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
Kirill Ustyantsev, Apr 27 2018
STATUS
approved