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T(n,k)=Number of nXk 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.
14

%I #4 Jan 13 2017 16:58:56

%S 0,0,0,0,1,0,1,6,6,0,2,34,68,29,0,6,104,239,376,122,0,13,251,618,1022,

%T 1492,468,0,29,535,1403,2452,3416,4988,1686,0,60,1076,2828,5400,7803,

%U 10112,15028,5807,0,122,2090,5482,10570,16875,22106,27635,42252,19338,0

%N T(n,k)=Number of nXk 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

%C Table starts

%C .0.....0......0......1......2.......6......13......29......60......122......241

%C .0.....1......6.....34....104.....251.....535....1076....2090.....3956.....7353

%C .0.....6.....68....239....618....1403....2828....5482...10342....19136....34907

%C .0....29....376...1022...2452....5400...10570...19892...36616....66354...118926

%C .0...122...1492...3416...7803...16875...32370...59669..107693...191953...339219

%C .0...468...4988..10112..22106...46610...87995..159317..282552...495655...864369

%C .0..1686..15028..27635..58005..119205..221212..394884..689397..1191475..2050466

%C .0..5807..42252..71419.144283..288527..526340..926077.1596265..2721514..4625355

%C .0.19338.113076.177320.344972..671451.1201939.2084979.3549039..5982952.10051523

%C .0.62731.291660.426696.800225.1515524.2661939.4546633.7645715.12749511.21211441

%H R. H. Hardin, <a href="/A281056/b281056.txt">Table of n, a(n) for n = 1..338</a>

%F Empirical for column k:

%F k=1: a(n) = a(n-1)

%F k=2: a(n) = 9*a(n-1) -30*a(n-2) +45*a(n-3) -30*a(n-4) +9*a(n-5) -a(n-6)

%F k=3: a(n) = 5*a(n-1) -6*a(n-2) -4*a(n-3) +8*a(n-4) for n>6

%F k=4: [order 12] for n>14

%F k=5: [order 13] for n>16

%F k=6: [order 18] for n>21

%F k=7: [order 19] for n>23

%F Empirical for row n:

%F n=1: a(n) = 3*a(n-1) -5*a(n-3) +3*a(n-5) +a(n-6)

%F n=2: [order 8] for n>14

%F n=3: [same order 8] for n>15

%F n=4: [order 9] for n>17

%F n=5: [same order 9] for n>18

%F n=6: [same order 9] for n>19

%F n=7: [same order 9] for n>20

%e Some solutions for n=4 k=4

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

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

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

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

%Y Row 1 is A055243(n-4).

%K nonn,tabl

%O 1,8

%A _R. H. Hardin_, Jan 13 2017