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A207268 Number of nX7 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 1 1 and 1 0 1 vertically 1
25, 625, 2141, 8327, 38911, 140295, 467686, 1623957, 5467589, 17779942, 57847658, 186862280, 594627012, 1880223340, 5915390781, 18465652946, 57306451587, 177068551553, 544446252694, 1666721759718, 5084288683371, 15456590300469 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A207269

LINKS

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

FORMULA

Empirical: a(n) = 11*a(n-1) -54*a(n-2) +216*a(n-3) -889*a(n-4) +2977*a(n-5) -8510*a(n-6) +25069*a(n-7) -66405*a(n-8) +153594*a(n-9) -368050*a(n-10) +821593*a(n-11) -1609293*a(n-12) +3316946*a(n-13) -6468261*a(n-14) +10971937*a(n-15) -20147157*a(n-16) +35163857*a(n-17) -52207053*a(n-18) +87915951*a(n-19) -139785106*a(n-20) +181957461*a(n-21) -289289211*a(n-22) +424118313*a(n-23) -480420806*a(n-24) +745259282*a(n-25) -1013368615*a(n-26) +980716070*a(n-27) -1545650812*a(n-28) +1947498910*a(n-29) -1558647255*a(n-30) +2631257150*a(n-31) -3050245541*a(n-32) +1912573548*a(n-33) -3721424748*a(n-34) +3923838434*a(n-35) -1753385708*a(n-36) +4394239753*a(n-37) -4162520500*a(n-38) +1086915329*a(n-39) -4318874276*a(n-40) +3645756520*a(n-41) -271419946*a(n-42) +3493357062*a(n-43) -2633648290*a(n-44) -270916251*a(n-45) -2280033769*a(n-46) +1562708364*a(n-47) +395555068*a(n-48) +1165613696*a(n-49) -752684244*a(n-50) -266379104*a(n-51) -446480616*a(n-52) +286392928*a(n-53) +110312752*a(n-54) +119783424*a(n-55) -81864192*a(n-56) -27286272*a(n-57) -20157696*a(n-58) +16008192*a(n-59) +3124224*a(n-60) +1658880*a(n-61) -1658880*a(n-62) for n>65

EXAMPLE

Some solutions for n=4

..0..0..1..0..0..1..0....0..0..1..0..0..1..0....0..1..0..0..1..0..1

..1..0..0..1..0..0..1....0..0..1..0..0..1..0....1..1..0..0..1..0..1

..0..1..0..0..1..0..0....0..0..1..0..0..1..0....0..1..0..0..1..0..0

..0..0..1..0..0..1..0....1..1..0..0..1..0..0....0..1..0..1..0..1..0

CROSSREFS

Sequence in context: A207687 A207345 A207487 * A208106 A207727 A207912

Adjacent sequences:  A207265 A207266 A207267 * A207269 A207270 A207271

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 16 2012

STATUS

approved

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Last modified May 24 16:36 EDT 2022. Contains 354042 sequences. (Running on oeis4.)