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A268902 Number of n X 6 0..2 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once. 1

%I

%S 240,9720,299088,8250912,214142760,5344944120,129834259704,

%T 3091414865040,72488795124312,1679265104747616,38520989302343760,

%U 876481043382776664,19806871824479466648,444994736265664134120,9947337685046673808176

%N Number of n X 6 0..2 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once.

%H R. H. Hardin, <a href="/A268902/b268902.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 50*a(n-1) - 805*a(n-2) + 4662*a(n-3) - 12150*a(n-4) + 14580*a(n-5) - 6561*a(n-6).

%F Empirical g.f.: 24*x*(10 - 95*x + 262*x^2 + 93*x^3 - 1485*x^4 + 1701*x^5) / (1 - 25*x + 90*x^2 - 81*x^3)^2. - _Colin Barker_, Jan 16 2019

%e Some solutions for n=2:

%e ..0..0..0..0..0..0. .1..2..2..2..1..2. .2..2..2..2..2..2. .2..1..2..2..2..2

%e ..0..1..0..1..1..2. .1..0..1..2..1..0. .2..1..1..2..1..0. .2..2..1..0..1..2

%Y Column 6 of A268904.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 15 2016

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Last modified September 25 15:54 EDT 2022. Contains 356986 sequences. (Running on oeis4.)