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Number of n element 0..1 arrays with each element the minimum of 7 adjacent elements of a random 0..1 array of n+6 elements.
1

%I #8 Jul 23 2018 08:43:50

%S 2,4,7,11,16,22,29,37,47,61,82,114,162,232,331,467,650,894,1220,1660,

%T 2262,3096,4261,5893,8175,11351,15747,21803,30121,41535,57210,78778,

%U 108521,149615,206456,285100,393865,544165,751675,1037963,1432772

%N Number of n element 0..1 arrays with each element the minimum of 7 adjacent elements of a random 0..1 array of n+6 elements.

%C Column 7 of A217839.

%H R. H. Hardin, <a href="/A217838/b217838.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) - a(n-2) + a(n-8).

%F Empirical g.f.: x*(2 + x^2 + x^3 + x^4 + x^5 + x^6 + x^7) / ((1 - x + x^4)*(1 - x - x^4)). - _Colin Barker_, Jul 23 2018

%e Some solutions for n=8:

%e ..0....0....1....0....0....0....0....0....1....1....0....0....0....0....0....0

%e ..1....1....0....0....0....1....0....0....1....1....0....0....0....0....1....0

%e ..1....1....0....0....1....1....0....1....0....1....1....0....0....0....1....0

%e ..1....1....0....1....0....1....1....1....0....1....1....0....0....1....1....0

%e ..1....1....0....1....0....1....1....0....0....1....1....0....1....1....0....0

%e ..1....1....0....1....0....0....1....0....0....1....0....0....1....0....0....0

%e ..1....0....0....1....0....0....1....0....0....0....0....0....1....0....0....1

%e ..1....0....0....0....0....0....1....0....0....0....0....0....0....0....0....0

%Y Cf. A217839.

%K nonn

%O 1,1

%A _R. H. Hardin_, Oct 12 2012