OFFSET
0,2
COMMENTS
180*atan(n)/Pi is an exact integer only for n = 0 and n = 1 (and n = -1). a(n) = 89 for n >= 58.
FORMULA
For all integers n, a(n) = floor(180*atan(n)/Pi) = -A140278(-n), where a negative term represents a fourth-quadrant angle. Terms shown are only for n >= 0.
EXAMPLE
a(1) = 45 degrees as that is the first-quadrant angle with tan(45 deg) = 1. a(2) = 63 degrees as 180*atan(2)/Pi = 63.4349... and floor(63.4349...) = 63.
PROG
(PARI) a(n) = floor(180*atan(n)/Pi)
CROSSREFS
KEYWORD
nonn
AUTHOR
Rick L. Shepherd, May 16 2008
STATUS
approved