A230944 Number of (n+3)X(3+3) 0..3 white square subarrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, and upper left element zero

76, 724, 8374, 85196, 854206, 8838040, 91616256, 944382122, 9735444252, 100434191824, 1036029240624, 10686275566528, 110228673309452, 1137013355879738, 11728259371943234, 120976628016491406

Offset

1,1

Comments

Column 3 of A230949

Links

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

Formula

Empirical: a(n) = 11*a(n-1) -23*a(n-2) +150*a(n-3) +309*a(n-4) -2148*a(n-5) +10102*a(n-6) -47494*a(n-7) -27771*a(n-8) -127963*a(n-9) -856209*a(n-10) -751900*a(n-11) +518927*a(n-12) +1522290*a(n-13) +5226896*a(n-14) +6396332*a(n-15) -6910959*a(n-16) -15629371*a(n-17) +577087*a(n-18) +12661958*a(n-19) +107867*a(n-20) -3633560*a(n-21) +898870*a(n-22) +447610*a(n-23) -220949*a(n-24) -31637*a(n-25) -855*a(n-26) +2592*a(n-27) +865*a(n-28) +42*a(n-29) +4*a(n-30)

Example

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

Crossrefs

Sequence in context: A185481 A007250 A137061 * A136963 A136964 A136962

Adjacent sequences: A230941 A230942 A230943 * A230945 A230946 A230947

Keyword

nonn

Author

R. H. Hardin, Nov 01 2013

Status

approved