cp's OEIS Frontend

A317106 Squares visited by a (1,3)-leaper on a spirally numbered board and moving to the lowest available unvisited square at each step, squares labelled >=1.

%I A317106 #17 Feb 06 2025 04:11:16
%S A317106 1,27,13,5,11,7,15,9,19,3,17,33,55,85,25,29,51,47,21,39,63,95,57,87,
%T A317106 125,49,23,41,67,35,59,89,53,31,61,37,69,43,77,113,71,45,73,107,149,
%U A317106 101,141,189,135,181,129,91,137,97,65,105,147,99,139,93,131,177,231
%N A317106 Squares visited by a (1,3)-leaper on a spirally numbered board and moving to the lowest available unvisited square at each step, squares labelled >=1.
%C A317106 Board is numbered with the square spiral:
%C A317106 .
%C A317106   17--16--15--14--13
%C A317106    |               |
%C A317106   18   5---4---3  12   .
%C A317106    |   |       |   |
%C A317106   19   6   1---2  11   .
%C A317106    |   |           |
%C A317106   20   7---8---9--10   .
%C A317106    |
%C A317106   21--22--23--24--25--26
%C A317106 .
%C A317106 The sequence is finite: at step 3723, square 7081 is visited, after which there are no unvisited squares within one move.
%H A317106 Daniël Karssen, <a href="/A317106/b317106.txt">Table of n, a(n) for n = 1..3723</a>
%H A317106 Daniël Karssen, <a href="/A317106/a317106.svg">Figure showing the first 46 steps of the sequence</a>
%H A317106 Daniël Karssen, <a href="/A317106/a317106_1.svg">Figure showing the complete sequence</a>
%F A317106 a(n) = A317105(n-1) + 1.
%Y A317106 Cf. A317105, A317108.
%K A317106 nonn,fini,full
%O A317106 1,2
%A A317106 _Daniël Karssen_, Jul 24 2018