A252559 - OEIS

%I #4 Dec 18 2014 09:51:12

%S 771,1107,1510,2443,4284,7755,13917,27182,51187,94813,189576,362736,

%T 678322,1360865,2614578,4907897,9838034,18931643,35616087,71259620,

%U 137248851,258672971,516507423,995487746,1879267853,3745133076

%N Number of (1+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 1 2 4 6 or 7 and every 3X3 column and antidiagonal sum not equal to 1 2 4 6 or 7

%C Row 1 of A252558

%H R. H. Hardin, <a href="/A252559/b252559.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 25*a(n-3) +2*a(n-4) -239*a(n-6) -43*a(n-7) -a(n-8) +1103*a(n-9) +334*a(n-10) +17*a(n-11) -2670*a(n-12) -1108*a(n-13) -84*a(n-14) +3919*a(n-15) +1405*a(n-16) +17*a(n-17) -4053*a(n-18) -354*a(n-19) +805*a(n-20) +3346*a(n-21) -1100*a(n-22) -1994*a(n-23) -2345*a(n-24) +2032*a(n-25) +2624*a(n-26) +1431*a(n-27) -2128*a(n-28) -2602*a(n-29) -817*a(n-30) +1501*a(n-31) +1921*a(n-32) +463*a(n-33) -754*a(n-34) -1063*a(n-35) -216*a(n-36) +276*a(n-37) +468*a(n-38) +81*a(n-39) -63*a(n-40) -135*a(n-41) -27*a(n-42) +27*a(n-44) for n>60

%e Some solutions for n=4

%e ..3..2..1..3..2..2....0..2..2..3..2..2....3..0..3..1..3..0....0..3..1..3..2..1

%e ..1..1..2..3..1..3....2..3..2..2..3..2....3..2..1..1..0..0....0..1..1..0..0..1

%e ..1..0..0..2..0..0....3..3..1..3..0..1....3..3..1..3..0..3....3..1..3..2..1..1

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 18 2014