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 A209383 #21 Oct 26 2024 04:07:55 %S A209383 1,1,2,4,10,23,63,155,448,1151,3450,9137,28134,76236,239712,661374, %T A209383 2115046,5921549,19203568,54422726,178585838,511343777,1694965469, %U A209383 4896195579,16371992897,47656781437,160578870274,470571482142,1596323368095,4705798878362,16059653893209 %N A209383 Meandric numbers for a river crossing up to 8 parallel roads at n points. %C A209383 Number of ways that a river (or directed line) that starts in the South and flows East can cross up to 8 parallel East-West roads n times. %C A209383 Sequence derived from list of solutions described in A206432. %H A209383 Andrew Howroyd, <a href="/A209383/b209383.txt">Table of n, a(n) for n = 0..36</a> %Y A209383 Cf. A005316 (sequence for one road; extensive references and links). %Y A209383 Cf. A076876 (sequence for two parallel roads). %Y A209383 Cf. A204352, A208062, A208126, A208452, A208453, A209383, A209621, A209622, A209626, A209656, A209657, A209660, A209707, A210344, A210478, A210567, A210592 (sequences for 3 to 19 parallel roads). %Y A209383 Cf. A206432 (sequence for unlimited number of parallel roads). %Y A209383 Cf. A076875, A076906, A076907. %K A209383 nonn %O A209383 0,3 %A A209383 _Robert Price_, May 07 2012 %E A209383 a(21)-a(36) from _Andrew Howroyd_, Dec 05 2015