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%I #14 Mar 17 2016 06:02:09
%S 60,90,108,120,129,135,140,144,147,150,152,154,156,158,159,160,161,
%T 162,163,164,164,165,166,166,167,167,168,168,168,169,169,169,170,170,
%U 170,171,171,171,171,171,172,172,172,172,172,173,173,173,173,173,173,173,173,174
%N Interior angle of a regular polygon of n sides, rounded to nearest integer.
%D Alexander Koeberlein, Elementary Geometry for College Students, 2nd Edition, Houghton Mifflin Company, Boston, 1999
%F a(n) = round(((n-2)*180)/n).
%e a(5) = (3*180)/5 = 108.
%e a(720) = 180; the maximum value. - _Robert G. Wilson v_, Mar 16 2016
%t f[n_] := Round[180 (n - 2)/n]; Array[f, 55, 3] (* _Robert G. Wilson v_, Mar 16 2016 *)
%o (PARI) a(n) = round((n-2)*180/n); \\ _Michel Marcus_, Aug 27 2013
%Y Cf. A100659.
%K easy,nonn
%O 3,1
%A Kristie Smith (kristie10spud(AT)hotmail.com), Apr 30 2002
%E More terms from _Michel Marcus_, Aug 27 2013