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A255094 Number of (n+2) X (1+2) 0..1 arrays with no 3 x 3 subblock diagonal sum 1 and no antidiagonal sum 1 and no row sum 1 and no column sum 1. 1

%I #8 Dec 18 2018 11:11:37

%S 36,77,179,419,991,2345,5537,13105,31063,73591,174311,412949,978301,

%T 2317617,5490567,13007447,30815207,73002717,172947085,409720065,

%U 970646871,2299510047,5447651751,12905753661,30574362581,72432161761

%N Number of (n+2) X (1+2) 0..1 arrays with no 3 x 3 subblock diagonal sum 1 and no antidiagonal sum 1 and no row sum 1 and no column sum 1.

%H R. H. Hardin, <a href="/A255094/b255094.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) - a(n-2) + 5*a(n-3) - 2*a(n-4) + 3*a(n-5) - 2*a(n-6) - 2*a(n-7) - 2*a(n-8) - 2*a(n-9) + 2*a(n-11) for n>12.

%F Empirical g.f.: x*(36 + 5*x + 61*x^2 - 42*x^3 + 19*x^4 - 67*x^5 - 58*x^6 - 52*x^7 - 26*x^8 + 24*x^9 + 38*x^10 - 2*x^11) / ((1 - x)*(1 - x - 5*x^3 - 3*x^4 - 6*x^5 - 4*x^6 - 2*x^7 + 2*x^9 + 2*x^10)). - _Colin Barker_, Dec 18 2018

%e Some solutions for n=4:

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

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

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

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

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

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

%Y Column 1 of A255101.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 14 2015

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Last modified March 1 17:48 EST 2024. Contains 370442 sequences. (Running on oeis4.)