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A252507 Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and column sum equal to 0 2 5 6 or 7 and every 3X3 diagonal and antidiagonal sum not equal to 0 2 5 6 or 7 1

%I #4 Dec 18 2014 06:53:29

%S 1262,1515,2055,3326,5508,9526,17709,33357,62632,119155,230081,444951,

%T 865104,1681217,3279686,6410134,12571858,24617069,48369787,95007820,

%U 187003788,367894926,725427778,1428661348,2819873256,5561285116

%N Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and column sum equal to 0 2 5 6 or 7 and every 3X3 diagonal and antidiagonal sum not equal to 0 2 5 6 or 7

%C Column 1 of A252514

%H R. H. Hardin, <a href="/A252507/b252507.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = -2*a(n-1) +a(n-2) +21*a(n-3) +44*a(n-4) +3*a(n-5) -167*a(n-6) -398*a(n-7) -244*a(n-8) +541*a(n-9) +1870*a(n-10) +2166*a(n-11) +191*a(n-12) -4546*a(n-13) -8621*a(n-14) -6995*a(n-15) +3369*a(n-16) +17737*a(n-17) +23621*a(n-18) +11388*a(n-19) -16181*a(n-20) -39969*a(n-21) -39148*a(n-22) -8036*a(n-23) +35376*a(n-24) +59826*a(n-25) +44517*a(n-26) -4051*a(n-27) -52799*a(n-28) -66099*a(n-29) -33679*a(n-30) +20761*a(n-31) +57309*a(n-32) +52424*a(n-33) +12871*a(n-34) -29613*a(n-35) -46287*a(n-36) -29416*a(n-37) +3586*a(n-38) +27436*a(n-39) +28338*a(n-40) +10553*a(n-41) -9495*a(n-42) -18317*a(n-43) -12920*a(n-44) -1337*a(n-45) +7278*a(n-46) +8319*a(n-47) +4329*a(n-48) -406*a(n-49) -2641*a(n-50) -2423*a(n-51) -1106*a(n-52) -10*a(n-53) +426*a(n-54) +428*a(n-55) +210*a(n-56) +57*a(n-57) -29*a(n-58) -36*a(n-59) -18*a(n-60) -6*a(n-61) for n>68

%e Some solutions for n=4

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 18 2014

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Last modified April 25 09:56 EDT 2024. Contains 371967 sequences. (Running on oeis4.)