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A069976
Interior angle of a regular polygon of n sides, rounded to nearest integer.
5
60, 90, 108, 120, 129, 135, 140, 144, 147, 150, 152, 154, 156, 158, 159, 160, 161, 162, 163, 164, 164, 165, 166, 166, 167, 167, 168, 168, 168, 169, 169, 169, 170, 170, 170, 171, 171, 171, 171, 171, 172, 172, 172, 172, 172, 173, 173, 173, 173, 173, 173, 173, 173, 174
OFFSET
3,1
REFERENCES
Alexander Koeberlein, Elementary Geometry for College Students, 2nd Edition, Houghton Mifflin Company, Boston, 1999
FORMULA
a(n) = round(((n-2)*180)/n).
EXAMPLE
a(5) = (3*180)/5 = 108.
a(720) = 180; the maximum value. - Robert G. Wilson v, Mar 16 2016
MATHEMATICA
f[n_] := Round[180 (n - 2)/n]; Array[f, 55, 3] (* Robert G. Wilson v, Mar 16 2016 *)
PROG
(PARI) a(n) = round((n-2)*180/n); \\ Michel Marcus, Aug 27 2013
CROSSREFS
Cf. A100659.
Sequence in context: A086975 A357686 A100659 * A110546 A378054 A335140
KEYWORD
easy,nonn
AUTHOR
Kristie Smith (kristie10spud(AT)hotmail.com), Apr 30 2002
EXTENSIONS
More terms from Michel Marcus, Aug 27 2013
STATUS
approved