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A223945 Number of n X 4 0..1 arrays with diagonals and antidiagonals unimodal and rows nondecreasing. 1

%I

%S 5,25,96,321,1062,3645,12856,45626,161604,571202,2018635,7138542,

%T 25257472,89382635,316317650,1119405165,3961434035,14019204346,

%U 49613421418,175580918227,621378416037,2199050475783,7782414885011

%N Number of n X 4 0..1 arrays with diagonals and antidiagonals unimodal and rows nondecreasing.

%C Column 4 of A223949.

%H R. H. Hardin, <a href="/A223945/b223945.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 5*a(n-1) - 5*a(n-2) - 2*a(n-3) + 7*a(n-4) - 2*a(n-5) - 4*a(n-6) - 61*a(n-7) + 29*a(n-8) + 8*a(n-9) + 8*a(n-10).

%F Empirical g.f.: x*(5 - 4*x^2 - 24*x^3 - 48*x^4 - 33*x^5 - 19*x^6 + 45*x^7 + 16*x^8 + 8*x^9) / (1 - 5*x + 5*x^2 + 2*x^3 - 7*x^4 + 2*x^5 + 4*x^6 + 61*x^7 - 29*x^8 - 8*x^9 - 8*x^10). - _Colin Barker_, Aug 24 2018

%e Some solutions for n=3:

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

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

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

%Y Cf. A223949.

%K nonn

%O 1,1

%A _R. H. Hardin_, Mar 29 2013

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Last modified March 30 10:09 EDT 2020. Contains 333125 sequences. (Running on oeis4.)