cp's OEIS Frontend

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.

A227626 Consider the spiral of Theodorus (A072895). This sequence is closely related to A224269 and gives the number of k successive revolutions such that the triangles are closer to 360 degrees than any previous triangles.

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%I A227626 #11 Sep 28 2013 16:17:18
%S A227626 1,2,4,6,22,30,45,53,211,242,429,554,917,1239,1738,2161,2986,3005,
%T A227626 3101,3307,4800,6385,7308,15148,16668,19287,28103,72754,143406,457425,
%U A227626 955117,1129313,2290339,7362039,11374333,11711400,11778444,11896240,14221855,31972242
%N A227626 Consider the spiral of Theodorus (A072895). This sequence is closely related to A224269 and gives the number of k successive revolutions such that the triangles are closer to 360 degrees than any previous triangles.
%H A227626 Herbert Kociemba, <a href="http://kociemba.org/themen/spirale/theodorus.html">The Spiral of Theodorus</a>
%t A227626 k=minDist=1; lst={}; K=-2.1577829966594462209291427868295777235; num[n_] := Module[{a=-(K/2)+n Pi,b}, b=a^2-1/6; If[Floor[b]==Floor[b+1/(144 a^2)], Floor[b], Undefined]] While[k<40000000, n=num[k]; If[!NumberQ[n], Print[k," Stop"]; Break[]]; a=2Pi-Mod[K+2 Sqrt[n]+1/(6 Sqrt[n]),2Pi]; b=Mod[K+2 Sqrt[n+1]+1/(6 Sqrt[n+1]),2Pi]; If[a<minDist && a<b, AppendTo[lst,k]; minDist=a;]; If[b<minDist && b<a, AppendTo[lst,k]; minDist=b;]; k++]; lst
%Y A227626 Cf. A072895, A224269.
%K A227626 nonn
%O A227626 1,2
%A A227626 _Herbert Kociemba_, Jul 18 2013