A203178 Number of n X 5 0..2 arrays with every 1 immediately preceded by 0 to the left or above, no 0 immediately preceded by a 0, and every 2 immediately preceded by 0 1 to the left or above.

3, 6, 41, 205, 952, 4654, 23083, 115377, 551208, 2757161, 13535075, 66032042, 327270427, 1600093371, 7879616025, 38759698990, 190148017740, 936372926748, 4597851371118, 22603571928513, 111146666196027, 546043267710074

Offset

1,1

Comments

Column 5 of A203181.

Links

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

Formula

Empirical: a(n) = 8*a(n-2) +116*a(n-3) +51*a(n-4) -167*a(n-5) -5304*a(n-6) -2099*a(n-7) -2525*a(n-8) +135828*a(n-9) +21391*a(n-10) +123514*a(n-11) -2093446*a(n-12) +97691*a(n-13) -1966033*a(n-14) +19493219*a(n-15) -3026365*a(n-16) +20145258*a(n-17) -113265090*a(n-18) +15159673*a(n-19) -114880900*a(n-20) +405552988*a(n-21) -19056386*a(n-22) +326124841*a(n-23) -748576479*a(n-24) -82472243*a(n-25) -466324510*a(n-26) +468742748*a(n-27) +186385862*a(n-28) +282899431*a(n-29) +170444820*a(n-30) -68888448*a(n-31) -45542936*a(n-32) -71161527*a(n-33) +37789114*a(n-34) -8127020*a(n-35) -13969563*a(n-36) +5855719*a(n-37) -3592899*a(n-38) -388368*a(n-39) +412490*a(n-40) -118958*a(n-41) +20064*a(n-42) -2340*a(n-43) for n>45.

Example

Some solutions for n=5
..0..1..0..1..0....0..1..0..1..2....0..1..0..1..2....0..1..2..0..1
..1..0..1..2..1....1..0..1..0..1....1..0..1..2..0....1..0..1..1..0
..0..1..2..0..1....2..1..2..1..0....2..1..0..1..1....0..1..2..2..1
..1..0..1..1..0....0..1..2..2..1....0..1..2..0..2....1..0..1..2..2
..0..1..0..2..1....1..0..1..2..2....1..0..1..2..0....0..1..0..1..0

Crossrefs

Cf. A203181.

Sequence in context: A372017 A208649 A371063 * A104271 A360830 A109491

Adjacent sequences: A203175 A203176 A203177 * A203179 A203180 A203181

Keyword

nonn

Author

R. H. Hardin, Dec 30 2011

Status

approved