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Number of 3 X n 0..1 arrays with no element unequal to a strict majority of its horizontal, diagonal and antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.
1

%I #6 Aug 19 2022 15:26:41

%S 4,4,8,38,90,305,902,2710,8376,25226,77145,235122,715882,2186483,

%T 6666846,20353268,62140942,189739429,579567532,1770391431,5409031357,

%U 16528102350,50508922108,154369025240,471828803722,1442250315610,4408832591287

%N Number of 3 X n 0..1 arrays with no element unequal to a strict majority of its horizontal, diagonal and antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.

%C Row 3 of A281715.

%H R. H. Hardin, <a href="/A281717/b281717.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-1) +8*a(n-2) -16*a(n-3) -46*a(n-4) +39*a(n-5) +121*a(n-6) -66*a(n-7) -185*a(n-8) +78*a(n-9) +216*a(n-10) -71*a(n-11) -182*a(n-12) +51*a(n-13) +107*a(n-14) -24*a(n-15) -43*a(n-16) +7*a(n-17) +10*a(n-18) -a(n-19) -a(n-20) for n>21.

%e Some solutions for n=4

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

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

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

%Y Cf. A281715.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 28 2017