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 A002667 M3171 N1286 #27 Apr 24 2025 17:35:12
%S A002667 3,73,8599,400091364,371853741549033970,
%T A002667 253461181173408820488703379557217678
%N A002667 Continued cotangent for Pi.
%D A002667 D. H. Lehmer, A cotangent analogue of continued fractions, Duke Math. J., 4 (1935), 323-340.
%D A002667 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
%D A002667 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H A002667 Harry J. Smith, <a href="/A002667/b002667.txt">Table of n, a(n) for n = 0..9</a>
%H A002667 D. H. Lehmer, <a href="/A002065/a002065_1.pdf">A cotangent analogue of continued fractions</a>, Duke Math. J., 4 (1935), 323-340. [Annotated scanned copy]
%H A002667 <a href="/index/Ph#Pi314">Index entries for sequences related to the number Pi</a>
%t A002667 Floor[NestList[(#*Floor[#]+1)/(#-Floor[#]) &, Pi, 5]] (* _Stefano Spezia_, Apr 24 2025 *)
%o A002667 (PARI) { default(realprecision, 10000); bn=vector(10); bn[1]=Pi; for(n=2, 10, bn[n]=(bn[n-1]*floor(bn[n-1]) + 1)/(bn[n-1] - floor(bn[n-1]))); for (n=1, 10, write("b002667.txt", n-1, " ", floor(bn[n]))); } \\ _Harry J. Smith_, May 04 2009
%K A002667 nonn
%O A002667 0,1
%A A002667 _N. J. A. Sloane_
%E A002667 More terms from _Jeffrey Shallit_