A258888 Number of (n+2)X(2+2) 0..1 arrays with no 3x3 subblock diagonal sum less than the antidiagonal sum or central row sum less than the central column sum

900, 2304, 4489, 10680, 23409, 51188, 104329, 216395, 430336, 849760, 1635841, 3133971, 5904900, 11044072, 20421361, 37522132, 68376361, 123865010, 222994489, 399409023, 711929124, 1263316100, 2233035025, 3931870085, 6900957184

Offset

1,1

Comments

Column 2 of A258894

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +4*a(n-2) -8*a(n-3) -2*a(n-5) -14*a(n-6) +34*a(n-7) +8*a(n-8) -8*a(n-9) +16*a(n-10) -58*a(n-11) -16*a(n-12) +14*a(n-13) -4*a(n-14) +48*a(n-15) +16*a(n-16) -6*a(n-17) -2*a(n-18) -18*a(n-19) -8*a(n-20) +2*a(n-23) +a(n-24) for n>27

Example

Some solutions for n=4
..1..1..0..1....0..1..0..0....1..1..0..0....1..1..0..1....1..0..1..0
..1..0..0..0....1..0..1..1....1..1..0..1....1..0..0..0....1..0..1..1
..1..0..0..1....0..0..0..1....1..0..1..0....0..0..0..1....0..1..0..1
..1..0..0..0....0..0..0..1....1..0..0..1....0..0..0..1....1..0..1..1
..0..0..0..1....0..0..0..1....0..0..0..1....0..0..0..1....0..0..0..1
..1..0..1..1....0..0..1..1....1..0..1..1....0..0..1..1....0..0..0..1

Crossrefs

Cf. A258894

Sequence in context: A336680 A074853 A162143 * A287800 A246887 A232556

Adjacent sequences: A258885 A258886 A258887 * A258889 A258890 A258891

Keyword

nonn

Author

R. H. Hardin, Jun 14 2015

Status

approved