A202984 Number of nX4 0..2 arrays with every nonzero element less than or equal to some NW, E or S neighbor

1, 323, 16854, 595202, 21925060, 838636921, 31806596079, 1202034287472, 45502473476990, 1723031444492823, 65229144680968466, 2469365733432760517, 93485721339386285227, 3539191690379523970536, 133986438561970657310866

Offset

1,2

Comments

Column 4 of A202988

Links

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

Formula

Empirical: a(n) = 81*a(n-1) -2650*a(n-2) +57534*a(n-3) -1006049*a(n-4) +14110042*a(n-5) -156374857*a(n-6) +1402546490*a(n-7) -10334764132*a(n-8) +62985132359*a(n-9) -322923725391*a(n-10) +1421986751544*a(n-11) -5431526055118*a(n-12) +18027170888654*a(n-13) -52074797977218*a(n-14) +130774015379513*a(n-15) -284194471655824*a(n-16) +533058630171692*a(n-17) -856584239568831*a(n-18) +1158365519069682*a(n-19) -1312541024650245*a(n-20) +1293014926780249*a(n-21) -1212934586216840*a(n-22) +1217489318140232*a(n-23) -1237465662520164*a(n-24) +1044800391623280*a(n-25) -676320450307792*a(n-26) +350467954059168*a(n-27) -248979873413760*a(n-28) +259811018830464*a(n-29) -152536902790464*a(n-30) +38173394664000*a(n-31) -7134333120000*a(n-32) +853776000000*a(n-33) for n>34

Example

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

Crossrefs

Sequence in context: A094409 A253708 A210056 * A346387 A110709 A298271

Adjacent sequences: A202981 A202982 A202983 * A202985 A202986 A202987

Keyword

nonn

Author

R. H. Hardin Dec 26 2011

Status

approved