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A208707 Number of n X 6 0..1 arrays with new values 0..1 introduced in row major order and no element equal to more than two of its immediate leftward or upward or right-upward antidiagonal neighbors. 1

%I #9 Jul 06 2018 08:11:44

%S 32,1268,52184,2142580,87985748,3613193828,148378294612,6093257064980,

%T 250223806647572,10275613313012692,421975152458430164,

%U 17328700863708613076,711615060447141699796,29222963581518749645012

%N Number of n X 6 0..1 arrays with new values 0..1 introduced in row major order and no element equal to more than two of its immediate leftward or upward or right-upward antidiagonal neighbors.

%C Column 6 of A208709.

%H R. H. Hardin, <a href="/A208707/b208707.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 45*a(n-1) - 168*a(n-2) + 272*a(n-3) - 324*a(n-4) + 240*a(n-5) - 64*a(n-6) for n>7.

%F Empirical g.f.: 4*x*(8 - 43*x + 125*x^2 - 345*x^3 + 508*x^4 - 572*x^5 + 400*x^6) / ((1 - x)*(1 - 44*x + 124*x^2 - 148*x^3 + 176*x^4 - 64*x^5)). - _Colin Barker_, Jul 06 2018

%e Some solutions for n=4:

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

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

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

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

%Y Cf. A208709.

%K nonn

%O 1,1

%A _R. H. Hardin_, Mar 01 2012

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Last modified March 28 17:42 EDT 2024. Contains 371254 sequences. (Running on oeis4.)