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%I #5 Feb 01 2015 10:39:51
%S 2384,10870,54212,183210,536906,1612832,4205934,10525070,25843648,
%T 60108505,134388526,293848960,621358505,1276346055,2565832463,
%U 5035276195,9660711323,18188928868,33596838971,60932752216,108732023416
%N Number of (n+2)X(2+2) 0..1 arrays with every 3X3 subblock sum of the four sums of the central row, central column, diagonal and antidiagonal nondecreasing horizontally and vertically
%C Column 2 of A254568
%H R. H. Hardin, <a href="/A254562/b254562.txt">Table of n, a(n) for n = 1..210</a>
%H R. H. Hardin, <a href="/A254562/a254562.txt">polynomial of degree 20 plus a quasipolynomial of degree 12 with period 6</a>
%F Empirical: a(n) = 7*a(n-1) -20*a(n-2) +41*a(n-3) -105*a(n-4) +246*a(n-5) -414*a(n-6) +708*a(n-7) -1371*a(n-8) +2105*a(n-9) -2834*a(n-10) +4537*a(n-11) -6526*a(n-12) +7449*a(n-13) -9750*a(n-14) +13221*a(n-15) -13299*a(n-16) +13728*a(n-17) -17446*a(n-18) +15730*a(n-19) -11297*a(n-20) +13013*a(n-21) -10296*a(n-22) +1287*a(n-23) -1287*a(n-25) +10296*a(n-26) -13013*a(n-27) +11297*a(n-28) -15730*a(n-29) +17446*a(n-30) -13728*a(n-31) +13299*a(n-32) -13221*a(n-33) +9750*a(n-34) -7449*a(n-35) +6526*a(n-36) -4537*a(n-37) +2834*a(n-38) -2105*a(n-39) +1371*a(n-40) -708*a(n-41) +414*a(n-42) -246*a(n-43) +105*a(n-44) -41*a(n-45) +20*a(n-46) -7*a(n-47) +a(n-48) for n>56
%F polynomial of degree 20 plus a quasipolynomial of degree 12 with period 6 for n>8 (see link above)
%e Some solutions for n=4
%e ..0..0..1..1....0..1..0..1....0..1..0..1....0..0..0..0....0..0..0..0
%e ..1..0..0..1....0..0..0..1....0..0..1..0....0..0..0..1....0..0..0..1
%e ..0..0..1..0....0..0..0..0....1..0..1..1....1..0..0..1....0..0..0..1
%e ..0..1..1..1....0..1..1..1....1..0..1..1....0..0..0..0....1..1..1..0
%e ..1..1..1..1....0..1..1..0....0..0..1..0....0..1..1..1....0..0..1..1
%e ..0..0..1..1....1..0..0..0....1..1..0..1....0..0..1..0....1..1..1..1
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 01 2015