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A207937 Number of n X 7 0..1 arrays avoiding 0 0 1 and 1 0 0 horizontally and 0 0 1 and 1 1 0 vertically. 1

%I

%S 35,1225,8977,38207,121313,319439,737575,1544037,2994871,5463725,

%T 9477733,15759955,25278917,39305795,59479787,87882217,127119915,

%U 180418417,251725529,345825799,468466441,626495255,828011087,1082527373,1401149311

%N Number of n X 7 0..1 arrays avoiding 0 0 1 and 1 0 0 horizontally and 0 0 1 and 1 1 0 vertically.

%C Column 7 of A207938.

%H R. H. Hardin, <a href="/A207937/b207937.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 8*a(n-1) - 28*a(n-2) + 56*a(n-3) - 70*a(n-4) + 56*a(n-5) - 28*a(n-6) + 8*a(n-7) - a(n-8).

%F Conjectures from _Colin Barker_, Jun 26 2018: (Start)

%F G.f.: x*(35 + 945*x + 157*x^2 - 1269*x^3 + 863*x^4 - 191*x^5 + 5*x^6 - x^7) / (1 - x)^8.

%F a(n) = (1260 + 4974*n - 32165*n^2 - 6041*n^3 + 51940*n^4 + 21091*n^5 + 2905*n^6 + 136*n^7) / 1260.

%F (End)

%e Some solutions for n=4:

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

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

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

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

%Y Cf. A207938.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 21 2012

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Last modified January 24 13:05 EST 2022. Contains 350538 sequences. (Running on oeis4.)