|
%I #24 Apr 05 2024 13:07:40
%S 8,14,26,48,90,168,316,592,1114,2090,3932,7382,13884,26076,49032,
%T 92110,173170,325360,611618,1149248,2160212,4059360,7629882,14338290,
%U 26949004,50644750,95185300,178883252,336200648,631835054,1187485194,2231705808
%N Number of zig-zag paths from top to bottom of a rectangle of width 8 with n rows.
%C Number of words of length n using an 8-symbol alphabet where neighboring letters are neighbors in the alphabet. - _Andrew Howroyd_, Apr 17 2017
%H Joseph Myers, <a href="http://www.polyomino.org.uk/publications/2008/bmo1-2009-q1.pdf">BMO 2008--2009 Round 1 Problem 1---Generalisation</a>
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (1,3,-2,-1).
%F G.f.: 2*x*(4+3*x-6*x^2-2*x^3)/((1-x)*(1-3*x^2-x^3)). - _Colin Barker_, May 10 2012
%t LinearRecurrence[{1, 3, -2, -1}, {8, 14, 26, 48}, 32] (* _Jean-François Alcover_, Oct 08 2017 *)
%Y Column 8 of A220062.
%Y Twice A090992.
%K easy,nonn
%O 1,1
%A _Joseph Myers_, Dec 24 2008
|
