A198523 Number of nX3 0..4 arrays with values 0..4 introduced in row major order and each element equal to no more than two horizontal and vertical neighbors

5, 193, 16714, 1877316, 222590953, 26670041125, 3201911378187, 384557171168810, 46189600128813487, 5547962760669962158, 666383179391895903794, 80041410904141273707361, 9614030302463648373863365

Offset

1,1

Comments

Column 3 of A198528

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

Empirical: a(n) = 140*a(n-1) -2296*a(n-2) -11502*a(n-3) +41183*a(n-4) +408760*a(n-5) +595837*a(n-6) -3718654*a(n-7) -13795951*a(n-8) -11064332*a(n-9) +29075688*a(n-10) +108107068*a(n-11) +134930012*a(n-12) -37607560*a(n-13) -266631136*a(n-14) -319325600*a(n-15) -322970496*a(n-16) -229207424*a(n-17) +130810368*a(n-18) +389159424*a(n-19) +272935936*a(n-20) +65761280*a(n-21) -8192000*a(n-22) -6356992*a(n-23) -786432*a(n-24) for n>25

Example

Some solutions for n=4
..0..0..0....0..0..0....0..0..0....0..0..0....0..0..1....0..0..0....0..0..1
..1..2..1....1..2..0....0..1..2....1..2..3....0..1..2....1..2..1....0..0..2
..3..0..0....3..2..4....2..1..3....4..0..2....2..0..2....3..0..3....3..1..1
..1..4..0....3..0..3....2..3..0....0..2..3....2..1..3....1..4..0....2..1..1

Crossrefs

Sequence in context: A240702 A240639 A198482 * A093154 A194572 A068793

Adjacent sequences: A198520 A198521 A198522 * A198524 A198525 A198526

Keyword

nonn

Author

R. H. Hardin Oct 26 2011

Status

approved