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A230651 Number of nX7 0..2 white square subarrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value 2-x(i,j).

%I A230651 #6 Jun 02 2025 08:44:06
%S A230651 0,63,231,11745,90393,3951657,31908483,1374288243,11150938215,
%T A230651 479621050353,3893231603781,167435671598913,1359174652590399,
%U A230651 58453268091967479,474501281118252903,20406595554618417837
%N A230651 Number of nX7 0..2 white square subarrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value 2-x(i,j).
%C A230651 Column 7 of A230652
%H A230651 R. H. Hardin, <a href="/A230651/b230651.txt">Table of n, a(n) for n = 1..210</a>
%F A230651 Empirical: a(n) = 390*a(n-2) -14687*a(n-4) +146138*a(n-6) -823339*a(n-8) -2774563*a(n-10) +26807114*a(n-12) -60400888*a(n-14) +106367378*a(n-16) -35490451*a(n-18) -7548040169*a(n-20) +1542760687*a(n-22) +7961883650*a(n-24) +3473400076*a(n-26) +61902164677*a(n-28) +25546220017*a(n-30) +84369583536*a(n-32) +75320917456*a(n-34) +42723111397*a(n-36) -5387877662*a(n-38) +926204972*a(n-40) -121037200*a(n-42) +10124352*a(n-44) +414720*a(n-46) for n>47
%e A230651 Some solutions for n=5
%e A230651 ..2..x..2..x..2..x..2....2..x..2..x..2..x..2....0..x..1..x..1..x..2
%e A230651 ..x..0..x..2..x..0..x....x..0..x..0..x..0..x....x..2..x..1..x..0..x
%e A230651 ..1..x..0..x..0..x..2....2..x..2..x..1..x..2....1..x..0..x..1..x..2
%e A230651 ..x..1..x..0..x..0..x....x..1..x..2..x..1..x....x..1..x..0..x..2..x
%e A230651 ..1..x..1..x..2..x..2....1..x..0..x..1..x..1....1..x..2..x..0..x..0
%K A230651 nonn
%O A230651 1,2
%A A230651 _R. H. Hardin_, Oct 27 2013