A235093 Number of (n+1) X (3+1) 0..5 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 4, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).

808, 1728, 3832, 9460, 23792, 63884, 173440, 491596, 1403944, 4134548, 12235728, 37057844, 112505216, 347784756, 1075280328, 3373236492, 10564408720, 33488371740, 105827385472, 337928612524, 1074606972584, 3449111677268

Offset

1,1

Comments

Column 3 of A235098.

Links

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

Formula

Empirical: a(n) = 7*a(n-1) +20*a(n-2) -239*a(n-3) +36*a(n-4) +3285*a(n-5) -4086*a(n-6) -23439*a(n-7) +45882*a(n-8) +91959*a(n-9) -251226*a(n-10) -184209*a(n-11) +783240*a(n-12) +99087*a(n-13) -1431666*a(n-14) +277611*a(n-15) +1499767*a(n-16) -513754*a(n-17) -855386*a(n-18) +293540*a(n-19) +256932*a(n-20) -54600*a(n-21) -32760*a(n-22).

Example

Some solutions for n=4:
  3 4 3 4     3 2 3 4     3 5 2 3     4 2 1 0     3 2 3 2
  4 1 4 1     5 0 5 2     4 2 3 0     3 5 0 3     2 5 2 5
  3 4 3 4     3 2 3 4     2 4 1 2     4 2 1 0     4 3 4 3
  0 5 0 5     0 3 0 5     4 2 3 0     3 5 0 3     2 5 2 5
  3 4 3 4     2 1 2 3     2 4 1 2     4 2 1 0     5 4 5 4

Crossrefs

Column 3 of A235098.

Sequence in context: A252523 A243858 A252682 * A259959 A332180 A160034

Adjacent sequences: A235090 A235091 A235092 * A235094 A235095 A235096

Keyword

nonn

Author

R. H. Hardin, Jan 03 2014

Status

approved