%I #39 Feb 05 2025 09:20:21
%S 1,41,1041,22193,433801,8057625,144762849,2540882465,43840779353,
%T 746649798473,12587443678705,210491254232465,3496816762316713,
%U 57778098654714361,950391251581267073,15574198350636963201,254405750326548970361,4144508602760970898729,67361936661916258817937
%N Number of 4 X n binary arrays with a path of adjacent 1's from top row to bottom row using only left, right, and downward steps.
%C Unlike A069362, does not allow upward steps.
%H <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (36,-413,1642,-2536,1152).
%F G.f.: x*(1 + 5*x - 22*x^2 + 8*x^3)/((1 - 16*x)*(1 - 20*x + 93*x^2 - 154*x^3 + 72*x^4)). - _Pontus von Brömssen_, Feb 05 2025
%e For example, here is one such 4 X 4 array:
%e 0001
%e 1111
%e 1010
%e 1100
%e The following 4 X 5 array is a non-example, as there is no path using only left, right, and downward steps:
%e 10000
%e 10111
%e 11101
%e 00001
%Y Row 4 of A369892.
%Y Cf. A069362, A359576.
%K nonn,easy
%O 1,2
%A _Caleb Stanford_, Feb 05 2024
%E More terms from _Pontus von Brömssen_, Feb 05 2025