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A203795
Number of (n+1) X 8 0..3 arrays with every 2 X 2 subblock having equal diagonal elements or equal antidiagonal elements.
1
13176688, 4648124656, 1928524187248, 850544485943152, 384592800378103840, 175775764083051254128, 80711089384087351043680, 37135548440809981904800432, 17101394039078940980498101504
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 736*a(n-1) -116937*a(n-2) -12426867*a(n-3) +4178336859*a(n-4) -229549937526*a(n-5) -13938527664693*a(n-6) +1613174838352614*a(n-7) -6723732191210460*a(n-8) -3793677200872904844*a(n-9) +95599725324289288461*a(n-10) +3859777069294163781375*a(n-11) -175883234732148783400074*a(n-12) -1127604951086881260961233*a(n-13) +149395638208862917351275363*a(n-14) -1033892597458959657891919695*a(n-15) -65115189067272464828690846946*a(n-16) +1056829432274215548108584808222*a(n-17) +12995819572886598923592766005771*a(n-18) -401418326962686889962466174676250*a(n-19) -75408497622170255314653808031028*a(n-20) +77315966655010275353231922612201270*a(n-21) -458718948293545282664294653235355927*a(n-22) -7585289102561591536802078832315960579*a(n-23) +88100667146325728820528796406666693382*a(n-24) +279406787466448529994322225809306016893*a(n-25) -7756597602801844120978790725010533011678*a(n-26) +11917271994459666452480589604703807129100*a(n-27) +360251695149893274225706916231106257284620*a(n-28) -1630702135427998280702938033460652535231836*a(n-29) -8262677976945773194122070699592054907734520*a(n-30) +69252740619493645331442195888539024231491332*a(n-31) +42695330216330532583568550886403815835318808*a(n-32) -1486051083602744564681540386137009488770601472*a(n-33) +2071723132960859787785128638131751992086307424*a(n-34) +16722398315826302669087059249437452518916764128*a(n-35) -48249586548340583335304865162559595080750566720*a(n-36) -84977318989579479597556175251746571942281000960*a(n-37) +452401440433271703886921299971645122112062531392*a(n-38) -332640223245202821535372045226851801599955200*a(n-39) -2059088639803358567647458862766796995367316060992*a(n-40) +1763414003267858518365253838606401394619553068288*a(n-41) +4262627779234949003713756946290627940910131324928*a(n-42) -6368805370398743427318122175970150831704599112192*a(n-43) -3010615988628329744518286685221830524289433417472*a(n-44) +8709930010449883401848650947324659794821143843328*a(n-45) -1320499203520677090351030779514008969277918259200*a(n-46) -4422085328389502021927737687875259869307251326976*a(n-47) +2060952587165352710451761433661025854002823077888*a(n-48) +344279773072798481183136658348279100136127856640*a(n-49) -363719625320940938161694811821016610189779271680*a(n-50) +66805802688719227378876255877513062195597934592*a(n-51) -3296781235252894469644900840938999555223977984*a(n-52) -92149204316651851213797165967299983293022208*a(n-53) +6125011525175334339050675029838669046349824*a(n-54).
EXAMPLE
Some solutions for n=4
..2..1..3..2..1..3..0..3....3..2..3..0..1..1..1..1....0..0..3..0..1..1..2..0
..1..0..1..3..2..1..3..3....2..1..2..3..0..1..2..1....2..0..0..0..0..1..1..2
..3..1..2..1..3..2..1..3....0..2..3..0..2..0..1..0....2..2..0..0..1..2..1..1
..0..3..1..2..1..3..2..1....2..0..2..3..0..2..0..2....3..2..2..0..0..1..3..1
..0..0..3..1..1..1..3..2....0..1..0..2..3..0..1..0....3..3..2..2..0..0..1..1
CROSSREFS
Column 7 of A203796.
Sequence in context: A274026 A344924 A344925 * A094801 A330678 A250831
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 05 2012
STATUS
approved