A204050 Number of (n+2)X4 0..3 arrays with every 3X3 subblock having equal diagonal elements or equal antidiagonal elements, and new values 0..3 introduced in row major order

10447, 112362, 756338, 5883499, 45689226, 361569647, 2777961511, 21501371450, 166160922266, 1291534099042, 10003568767059, 77546108106626, 600524809842067, 4655276167460819, 36072762678121778, 279581381767181194

Offset

1,1

Comments

Column 2 of A204056

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 8*a(n-1) +5*a(n-2) -99*a(n-3) +724*a(n-4) -2536*a(n-5) -3590*a(n-6) +1687*a(n-7) +11959*a(n-8) +163995*a(n-9) +260790*a(n-10) -1081279*a(n-11) +60097*a(n-12) -364566*a(n-13) -8610867*a(n-14) +6484656*a(n-15) +14892705*a(n-16) +9662463*a(n-17) -7454322*a(n-18) -21790782*a(n-19) -17972280*a(n-20) +16159257*a(n-21) +13997529*a(n-22) -3470769*a(n-23) +1062882*a(n-24) -2539107*a(n-25) +531441*a(n-26) for n>27

Example

Some solutions for n=3
..0..0..0..0....0..1..2..2....0..0..0..0....0..1..0..0....0..0..0..0
..0..0..0..0....1..2..1..0....0..0..0..0....2..0..0..3....0..0..0..0
..0..0..0..0....2..1..2..1....0..0..0..0....3..0..0..0....0..0..0..0
..0..0..0..0....0..2..1..2....1..0..0..0....0..3..0..0....0..0..0..0
..0..0..1..0....0..3..2..1....1..0..0..0....1..3..3..0....1..2..0..0

Crossrefs

Sequence in context: A010082 A068759 A183787 * A114126 A171352 A237179

Adjacent sequences: A204047 A204048 A204049 * A204051 A204052 A204053

Keyword

nonn

Author

R. H. Hardin Jan 09 2012

Status

approved