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A207246 Number of 6Xn 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 0 1 0 vertically 1
21, 441, 2491, 13494, 58026, 197256, 683257, 2037721, 5952936, 16732138, 44859931, 119159921, 307712676, 784050794, 1976285122, 4919758858, 12172588913, 29902600211, 73076993300, 177908921984, 431510277616, 1043914139326 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 6 of A207242

LINKS

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

FORMULA

Empirical: a(n) = 8*a(n-1) -12*a(n-2) -50*a(n-3) +95*a(n-4) +336*a(n-5) -588*a(n-6) -1487*a(n-7) +2028*a(n-8) +5458*a(n-9) -4964*a(n-10) -14733*a(n-11) +7983*a(n-12) +28710*a(n-13) -8764*a(n-14) -38038*a(n-15) +13329*a(n-16) +25576*a(n-17) -34894*a(n-18) +4797*a(n-19) +85079*a(n-20) -38346*a(n-21) -123180*a(n-22) +57099*a(n-23) +106641*a(n-24) -85944*a(n-25) -32414*a(n-26) +135057*a(n-27) -63771*a(n-28) -139446*a(n-29) +104392*a(n-30) +117031*a(n-31) -151465*a(n-32) +920*a(n-33) +105470*a(n-34) -49741*a(n-35) -96933*a(n-36) +117706*a(n-37) +13032*a(n-38) -80359*a(n-39) +20007*a(n-40) +50040*a(n-41) -44770*a(n-42) -18399*a(n-43) +51353*a(n-44) -23402*a(n-45) -7892*a(n-46) +3053*a(n-47) +19099*a(n-48) -27640*a(n-49) +17674*a(n-50) -6057*a(n-51) +5305*a(n-52) -9666*a(n-53) +10300*a(n-54) -6951*a(n-55) +3382*a(n-56) -2268*a(n-57) +2458*a(n-58) -2163*a(n-59) +1388*a(n-60) -658*a(n-61) +348*a(n-62) -290*a(n-63) +219*a(n-64) -126*a(n-65) +50*a(n-66) -18*a(n-67) +12*a(n-68) -8*a(n-69) +4*a(n-70) -a(n-71)

EXAMPLE

Some solutions for n=4

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

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

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

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

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

CROSSREFS

Sequence in context: A207417 A207389 A207517 * A208167 A207066 A207121

Adjacent sequences:  A207243 A207244 A207245 * A207247 A207248 A207249

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 16 2012

STATUS

approved

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Last modified February 27 19:10 EST 2020. Contains 332308 sequences. (Running on oeis4.)