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A206646
Number of nX4 0..2 arrays with no occurrence of three equal elements in a row horizontally or vertically, and new values 0..2 introduced in row major order
1
11, 726, 30145, 1414023, 64166392, 2937839117, 134185561617, 6132878568838, 280251085790917, 12807094593314569, 585259459542315836, 26745316717727432935, 1222212300246808969679, 55852891619111893009138
OFFSET
1,1
COMMENTS
Column 4 of A206650
LINKS
FORMULA
Empirical: a(n) = 32*a(n-1) +710*a(n-2) -2541*a(n-3) -58297*a(n-4) -84383*a(n-5) +1296007*a(n-6) +19243146*a(n-7) -64100368*a(n-8) -141520351*a(n-9) -1609731097*a(n-10) +10556269325*a(n-11) -1431133322*a(n-12) -12602899768*a(n-13) -179460913672*a(n-14) +178320472600*a(n-15) +457844879304*a(n-16) +595922150908*a(n-17) -899085837736*a(n-18) -1898963195864*a(n-19) +193666862880*a(n-20) -8060600474896*a(n-21) -2249882888064*a(n-22) +8612081648096*a(n-23) +44225847784512*a(n-24) +38378919985472*a(n-25) +69536075213440*a(n-26) +42924805038720*a(n-27) -257043560481280*a(n-28) -614121185315072*a(n-29) -507075609021440*a(n-30) +75385866295808*a(n-31) -87056512295936*a(n-32) +1144300402821120*a(n-33) +2589943188324352*a(n-34) +1127593852403712*a(n-35) +1688975302180864*a(n-36) +2333630124032000*a(n-37) +315178737991680*a(n-38) +277744289841152*a(n-39) +675889502224384*a(n-40) +3390499192832*a(n-41) -29496566611968*a(n-42) +58586896007168*a(n-43) -11515063173120*a(n-44) -4815623028736*a(n-45) -5027125002240*a(n-46) -1599472664576*a(n-47) +914224054272*a(n-48) -855101145088*a(n-49) -3758096384*a(n-50) -53687091200*a(n-51) -60129542144*a(n-52) +21474836480*a(n-53)
EXAMPLE
Some solutions for n=4
..0..0..1..1....0..1..0..2....0..1..0..2....0..1..2..1....0..0..1..1
..2..0..1..0....1..1..2..2....1..2..2..1....2..2..1..2....1..1..2..0
..0..2..2..1....1..2..2..1....1..0..1..1....0..2..2..0....0..1..2..2
..2..0..0..1....2..1..0..1....0..0..2..0....0..0..2..1....0..0..1..2
CROSSREFS
Sequence in context: A204974 A204701 A267954 * A267908 A180740 A330309
KEYWORD
nonn
AUTHOR
R. H. Hardin Feb 11 2012
STATUS
approved