This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A069976 #14 Mar 17 2016 06:02:09 %S A069976 60,90,108,120,129,135,140,144,147,150,152,154,156,158,159,160,161, %T A069976 162,163,164,164,165,166,166,167,167,168,168,168,169,169,169,170,170, %U A069976 170,171,171,171,171,171,172,172,172,172,172,173,173,173,173,173,173,173,173,174 %N A069976 Interior angle of a regular polygon of n sides, rounded to nearest integer. %D A069976 Alexander Koeberlein, Elementary Geometry for College Students, 2nd Edition, Houghton Mifflin Company, Boston, 1999 %F A069976 a(n) = round(((n-2)*180)/n). %e A069976 a(5) = (3*180)/5 = 108. %e A069976 a(720) = 180; the maximum value. - _Robert G. Wilson v_, Mar 16 2016 %t A069976 f[n_] := Round[180 (n - 2)/n]; Array[f, 55, 3] (* _Robert G. Wilson v_, Mar 16 2016 *) %o A069976 (PARI) a(n) = round((n-2)*180/n); \\ _Michel Marcus_, Aug 27 2013 %Y A069976 Cf. A100659. %K A069976 easy,nonn %O A069976 3,1 %A A069976 Kristie Smith (kristie10spud(AT)hotmail.com), Apr 30 2002 %E A069976 More terms from _Michel Marcus_, Aug 27 2013