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 A038807 #24 Feb 16 2025 08:32:38 %S A038807 2,3,5,10,9,20,46,83,12,24,23,36,79,124,172,56,119,61,169,17,42,84, %T A038807 232,285,596,1186,3190,6857,14225,12495,30482,45827,79090,144112, %U A038807 423486,1087497,2443796,628733,871389,1199242,2787410,7975876 %N A038807 Future of the smallest-perizeroin komet in Kimberling's expulsion array (A035486). %C A038807 Could the komet be a planit? %D A038807 D. Gale, Mathematical Entertainments: "Careful Card-Shuffling and Cutting Can Create Chaos," The Mathematical Intelligencer, vol. 14, no. 1, 1992, pages 54-56. %D A038807 D. Gale, Tracking the Automatic Ant and Other Mathematical Explorations, A Collection of Mathematical Entertainments Columns from The Mathematical Intelligencer, Springer, 1998. %D A038807 Hans Havermann, Algorithm, #4, 1992, p. 2. %H A038807 Enrique Pérez Herrero, <a href="/A038807/b038807.txt">Table of n, a(n) for n = 0..74</a> %H A038807 Lars Blomberg & Hans Havermann, <a href="https://spreadsheets.google.com/ccc?key=0Ars3II3ElHF_dHN4aVhseV90WDJSSTlJQXJQVzl5cGc&hl=en">komets & planits (250 kometary path fragments)</a> %H A038807 Hans Havermann, <a href="http://chesswanks.com/txt/ARecreationalEndeavour.txt">A Recreational Endeavour</a> %H A038807 Clark Kimberling, <a href="https://cms.math.ca/crux/backfile/Crux_v17n02_Feb.pdf">Problem 1615</a>, Crux Mathematicorum, Vol. 17 (2) 44 1991; <a href="https://cms.math.ca/crux/backfile/Crux_v18n03_Mar.pdf">Solution to Problem 1615</a>, Crux Mathematicorum, Vol. 18, March 1992, pp. 82-83. %H A038807 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/KimberlingSequence.html">Kimberling Sequence</a> %F A038807 a(0) = 2; a(n) = a(n-1)-th term in Kimberling's expulsion array (A007063). %t A038807 K[i_, j_] := i + j - 1 /; (j >= 2 i - 3); %t A038807 K[i_, j_] := K[i - 1, i - (j + 2)/2] /; (EvenQ[j] && (j < 2 i - 3)); %t A038807 K[i_, j_] := K[i - 1, i + (j - 1)/2] /; (OddQ[j] && (j < 2 i - 3)); %t A038807 K[i_] := K[i] = K[i, i]; SetAttributes[K, Listable]; %t A038807 A007063[i_] := K[i]; %t A038807 A038807[1] := 2; %t A038807 A038807[n_] := A007063[A038807[n - 1]]; %t A038807 ReleaseHold[Table[A038807[n], {n, 1, 35}]] %t A038807 (* _Enrique Pérez Herrero_, Jan 11 2023 *) %Y A038807 Cf. A007063, A006852, A038834. %K A038807 nonn %O A038807 0,1 %A A038807 _Hans Havermann_