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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 1
55296, 2973696, 160435446, 8643947616, 465761252736, 25096321973400, 1352264628934656, 72863901465993216, 3926116038018167136, 211550413039991414784, 11398943982115046916096, 614207848185760126372224 (list; graph; refs; listen; history; text; internal format)
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

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Last modified October 23 11:52 EDT 2021. Contains 348212 sequences. (Running on oeis4.)