A344421 Number of lattice points (x,y) in the region bounded by 0 < y < n*sin(x*Pi/n) for 0 < x < n.

0, 1, 4, 7, 12, 19, 28, 37, 46, 59, 72, 85, 102, 117, 136, 155, 176, 195, 220, 247, 272, 299, 324, 355, 388, 421, 450, 485, 520, 559, 600, 637, 678, 719, 766, 807, 856, 897, 952, 999, 1052, 1101, 1156, 1215, 1266, 1327, 1380, 1445, 1504, 1569, 1630, 1695, 1764

Offset

1,3

Links

Table of n, a(n) for n=1..53.

Prog

(Python)
from sympy import sin, floor, pi
def A344421(n): return sum(floor(n*sin(x*pi/n))-int((n*sin(x*pi/n)).is_integer == True) for x in range(1, n)) # Chai Wah Wu, May 19 2021

Crossrefs

Sequence in context: A007333 A097536 A293829 * A022809 A297554 A188554

Adjacent sequences: A344418 A344419 A344420 * A344422 A344423 A344424

Keyword

nonn

Author

Wesley Ivan Hurt, May 17 2021

Extensions

More terms from Chai Wah Wu, May 19 2021

Status

approved