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A250956 T(n,k)=Number of (n+1)X(k+1) 0..1 arrays with no 2X2 subblock having its maximum diagonal element less than its minimum antidiagonal element 7

%I #4 Nov 28 2014 21:04:01

%S 15,56,56,209,392,209,780,2744,2744,780,2911,19208,36016,19208,2911,

%T 10864,134456,472712,472712,134456,10864,40545,941192,6204344,

%U 11633448,6204344,941192,40545,151316,6588344,81431944,286298344,286298344

%N T(n,k)=Number of (n+1)X(k+1) 0..1 arrays with no 2X2 subblock having its maximum diagonal element less than its minimum antidiagonal element

%C Table starts

%C .....15.......56.........209...........780.............2911..............10864

%C .....56......392........2744.........19208...........134456.............941192

%C ....209.....2744.......36016........472712..........6204344...........81431944

%C ....780....19208......472712......11633448........286298344.........7045780240

%C ...2911...134456.....6204344.....286298344......13211127617.......609622239024

%C ..10864...941192....81431944....7045780240.....609622239024.....52746349035592

%C ..40545..6588344..1068793208..173396103624...28130774228952...4563772381621072

%C .151316.46118408.14027896712.4267264603784.1298083303266168.394871276236514256

%H R. H. Hardin, <a href="/A250956/b250956.txt">Table of n, a(n) for n = 1..759</a>

%F Empirical for column k:

%F k=1: a(n) = 4*a(n-1) -a(n-2)

%F k=2: a(n) = 7*a(n-1)

%F k=3: a(n) = 15*a(n-1) -24*a(n-2) -8*a(n-3)

%F k=4: a(n) = 27*a(n-1) -57*a(n-2) -46*a(n-3) +30*a(n-4)

%F k=5: [order 7]

%F k=6: [order 9]

%F k=7: [order 16]

%e Some solutions for n=3 k=4

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

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

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

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

%Y Column 1 is A001353(n+2)

%Y Column 2 is A003950(n+1)

%K nonn,tabl

%O 1,1

%A _R. H. Hardin_, Nov 28 2014

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Last modified April 19 15:11 EDT 2024. Contains 371794 sequences. (Running on oeis4.)