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 A255575 #23 May 23 2024 00:50:03 %S A255575 1,1,1,2,2,3,4,5,7,9,12,15,20,26,33,43,56,72,92,119,153,197,253,325, %T A255575 419,539,693,891,1146,1474,1896,2439,3136,4034,5188,6672,8581,11036, %U A255575 14194,18254,23476,30192,38830,49938,64225,82598,106227,136616,175698,225961,290603,373737 %N A255575 a(n) = floor(((sqrt(sqrt(3))^3)/sqrt(Pi))^n). %C A255575 Inspired by A255405, but starting with a unit circle and an equilateral triangle whose area is equal to Pi. %C A255575 a(n) is the curvature (rounded down) of the n-th nested circle. See illustration in the links. %H A255575 G. C. Greubel, <a href="/A255575/b255575.txt">Table of n, a(n) for n = 0..5000</a> %H A255575 Kival Ngaokrajang, <a href="/A255575/a255575.pdf">Illustration of initial terms</a>. %F A255575 a(n) = floor(((sqrt(sqrt(3))^3)/sqrt(Pi))^n). %p A255575 A255575:=n->floor(((sqrt(sqrt(3))^3)/sqrt(Pi))^n): seq(A255575(n), n=0..70); # _Wesley Ivan Hurt_, Apr 28 2017 %t A255575 Table[Floor[(Sqrt[Sqrt[3]]^3/Sqrt[Pi])^n], {n, 51}] (* _Michael De Vlieger_, Feb 25 2015 *) %o A255575 (PARI){for(n=0,100,a=floor(((sqrt(sqrt(3))^3)/sqrt(Pi))^n);print1(a,", "))} %Y A255575 Cf. A255405. %K A255575 nonn,easy %O A255575 0,4 %A A255575 _Kival Ngaokrajang_, Feb 25 2015