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 A380371 #32 Jan 31 2025 04:28:19 %S A380371 0,0,0,0,1,2,3,5,8,12,17,23,29,38,47,58,70,84,100,117,136,158,181,206, %T A380371 234,264,296,330,368,407,450,494,542,593,646,702,761,823,889,957,1028, %U A380371 1102,1180,1261,1344,1431,1522,1615,1712,1812,1915,2021,2130,2243,2359 %N A380371 a(n) is the integer part of the area of a rhombus with side n and angle n degrees. %C A380371 The angle n ranges 0 to 180 inclusive. %C A380371 Terms increase to a maximum 12951 at n = 131 and then decrease. %H A380371 Nicolay Avilov, <a href="/A380371/b380371.txt">Table of n, a(n) for n = 0..180</a> %F A380371 a(n) = floor(n^2*sin(Pi*n/180)). %e A380371 a(30) = 30*30*sin(30 degrees) = 450. %e A380371 a(90) = 8100 is the area of a square with a side of 90. %K A380371 nonn,easy,fini,full %O A380371 0,6 %A A380371 _Nicolay Avilov_, Jan 23 2025