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

11, 726, 30145, 1414023, 64166392, 2937839117, 134185561617, 6132878568838, 280251085790917, 12807094593314569, 585259459542315836, 26745316717727432935, 1222212300246808969679, 55852891619111893009138

Offset

1,1

Comments

Column 4 of A206650

Links

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

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

Adjacent sequences: A206643 A206644 A206645 * A206647 A206648 A206649

Keyword

nonn

Author

R. H. Hardin Feb 11 2012

Status

approved