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A204105 Number of (n+1)X8 0..2 arrays with column and row pair sums b(i,j)=a(i,j)+a(i,j-1) and c(i,j)=a(i,j)+a(i-1,j) such that b(i,j)*b(i-1,j)-c(i,j)*c(i,j-1) is nonzero 1
147456, 6718464, 306110016, 14683622976, 710001723456, 34589078037504, 1688734588654656, 82560206915726400, 4038274515214039104, 197577183499716614400, 9667741514059886432256, 473082597717729121382976 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Also 0..2 arrays with no 2X2 subblock having equal diagonal elements or equal antidiagonal elements

LINKS

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

FORMULA

Empirical: a(n) = 81*a(n-1) -990*a(n-2) -55557*a(n-3) +1308051*a(n-4) +9877815*a(n-5) -472364460*a(n-6) +943100415*a(n-7) +77404069476*a(n-8) -518255160660*a(n-9) -6362605755783*a(n-10) +72333960423075*a(n-11) +223601505317082*a(n-12) -5264665776830025*a(n-13) +3575284914586527*a(n-14) +225704467607414148*a(n-15) -691301950951353183*a(n-16) -5753524457427090471*a(n-17) +31302036027799741413*a(n-18) +76304508958149193188*a(n-19) -780598320639827527251*a(n-20) -32107509630606372660*a(n-21) +11916298097181567343665*a(n-22) -16999232257151001851004*a(n-23) -110708791324500349192293*a(n-24) +303730479433392729885693*a(n-25) +555754575465898156952694*a(n-26) -2737618881639491778320259*a(n-27) -584755510344811831795446*a(n-28) +14407869192888759424255026*a(n-29) -9579065689150601713125282*a(n-30) -44620541811711898638722874*a(n-31) +59888834204786049381681870*a(n-32) +75210686676036004338582552*a(n-33) -168955611080998044775817142*a(n-34) -43167918621829199898820959*a(n-35) +262083277346193044061068880*a(n-36) -64367087618676610768687146*a(n-37) -218976915013228373921343981*a(n-38) +130739067080067867741115677*a(n-39) +78915491598396738245792607*a(n-40) -84109173336513103888007001*a(n-41) +3118769447215496774534127*a(n-42) +17814505620501527202817290*a(n-43) -6540848332303545808795602*a(n-44) +717897987691852588770249*a(n-45)

EXAMPLE

Some solutions for n=5

..0..0..0..2..2..0..2..2....1..2..1..1..0..2..1..1....1..1..1..0..2..1..2..1

..2..2..1..1..1..1..1..1....0..0..0..2..0..2..0..2....2..0..2..0..2..1..2..1

..1..0..0..2..2..2..2..2....1..1..1..1..0..1..0..2....2..0..1..0..2..1..2..1

..1..2..1..1..0..0..0..1....2..2..2..2..2..2..0..1....2..0..1..0..2..0..2..0

..0..0..0..2..2..1..2..1....1..0..0..0..0..1..0..2....1..0..1..0..1..0..1..1

..1..1..1..1..0..0..2..1....1..2..1..1..2..1..0..2....1..0..1..0..1..0..2..0

CROSSREFS

Sequence in context: A004670 A111044 A189789 * A015317 A195363 A224424

Adjacent sequences:  A204102 A204103 A204104 * A204106 A204107 A204108

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 10 2012

STATUS

approved

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Last modified August 21 10:21 EDT 2018. Contains 313937 sequences. (Running on oeis4.)