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R. H. Hardin, <a href="/A297461/b297461.txt">Table of n, a(n) for n = 1..210</a>
allocated for R. H. Hardin
Number of 5Xn 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 0 or 2 neighboring 1s.
32, 120, 1652, 9774, 97005, 693884, 6088511, 46944276, 392535101, 3118759741, 25587588782, 205730539432, 1675286670914, 13533370289499, 109877296946086, 889273550010333, 7211533560114492, 58408475650808548, 473441572842310456
1,1
Row 5 of A297457.
Empirical: a(n) = 9*a(n-1) +25*a(n-2) -300*a(n-3) +190*a(n-4) +1036*a(n-5) -2513*a(n-6) +22460*a(n-7) -37310*a(n-8) -37759*a(n-9) +114450*a(n-10) -509961*a(n-11) +255438*a(n-12) +1144003*a(n-13) +1351722*a(n-14) +2846459*a(n-15) -6588847*a(n-16) -11171903*a(n-17) -1935014*a(n-18) +5860087*a(n-19) +22836946*a(n-20) +11156919*a(n-21) -18405627*a(n-22) -7467708*a(n-23) +2121469*a(n-24) -5003462*a(n-25) -927919*a(n-26) +3006648*a(n-27) +863641*a(n-28) -357454*a(n-29) -265914*a(n-30) -33568*a(n-31) +31636*a(n-32) +9112*a(n-33)
Some solutions for n=5
..0..0..1..1..1. .0..0..0..1..0. .0..1..0..0..0. .1..0..0..0..1
..0..0..0..1..0. .1..0..0..0..0. .1..1..1..0..0. .1..0..1..0..0
..1..0..0..1..0. .1..0..1..0..1. .0..0..0..0..0. .0..0..1..0..0
..0..0..0..0..0. .1..0..1..0..0. .1..1..0..0..1. .0..0..0..0..0
..1..0..0..1..0. .0..0..1..0..1. .1..1..0..0..0. .1..0..0..0..1
Cf. A297457.
allocated
nonn
R. H. Hardin, Dec 30 2017
approved
editing
allocated for R. H. Hardin
allocated
approved