A204776 Number of (n+2)X4 0..2 arrays with no 3X3 subblock having three equal diagonal elements or three equal antidiagonal elements, and new values 0..2 introduced in row major order

55296, 2973696, 160435446, 8643947616, 465761252736, 25096321973400, 1352264628934656, 72863901465993216, 3926116038018167136, 211550413039991414784, 11398943982115046916096, 614207848185760126372224

Offset

1,1

Comments

Column 2 of A204782

Links

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

Formula

Empirical: a(n) = 60*a(n-1) -288*a(n-2) -1444*a(n-3) -44368*a(n-4) +65024*a(n-5) -499024*a(n-6) +56284096*a(n-7) -203825408*a(n-8) +40641728*a(n-9) -106533120*a(n-10) +1206795264*a(n-11) -3244800*a(n-12) +3778118656*a(n-13) -13362151424*a(n-14) +8470860800*a(n-15) -10623004672*a(n-16) -4639195136*a(n-17) -30966444032*a(n-18) +53504131072*a(n-19) +15954542592*a(n-20) +342269640704*a(n-21) -490836787200*a(n-22) +704553680896*a(n-23) +880191471616*a(n-24) +622950612992*a(n-25) -4886632595456*a(n-26) -4635586723840*a(n-27) -25507642998784*a(n-28) +57332310474752*a(n-29) -8230767951872*a(n-30) -2624225017856*a(n-31) -4702989189120*a(n-32) -67645734912*a(n-33) -219043332096*a(n-34) +601295421440*a(n-35) -68719476736*a(n-36)

Example

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

Crossrefs

Sequence in context: A237732 A251164 A253148 * A237485 A092008 A190384

Adjacent sequences: A204773 A204774 A204775 * A204777 A204778 A204779

Keyword

nonn

Author

R. H. Hardin Jan 19 2012

Status

approved