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A232926 Number of 7Xn 0..2 arrays with no element x(i,j) adjacent to value 2-x(i,j) horizontally, diagonally or antidiagonally 1
2187, 4374, 106494, 1502736, 28178262, 459797904, 8119777890, 137439977160, 2384509133094, 40805841270468, 703918817382702, 12088079956487724, 208129904626404774, 3578168317715969412, 61569288080709446478 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 7 of A232920

LINKS

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

FORMULA

Empirical: a(n) = 15*a(n-1) +211*a(n-2) -2863*a(n-3) -13429*a(n-4) +203167*a(n-5) +281913*a(n-6) -7273959*a(n-7) +2536559*a(n-8) +145820567*a(n-9) -211890258*a(n-10) -1707543577*a(n-11) +3980736037*a(n-12) +11821765895*a(n-13) -39503723461*a(n-14) -45891971184*a(n-15) +241882321639*a(n-16) +65778053431*a(n-17) -978590162431*a(n-18) +246879014309*a(n-19) +2718479809492*a(n-20) -1652020665317*a(n-21) -5304510492989*a(n-22) +4695056741311*a(n-23) +7353393608676*a(n-24) -8375817160636*a(n-25) -7242062931643*a(n-26) +10268995022275*a(n-27) +4987531095051*a(n-28) -8951397463580*a(n-29) -2288267915190*a(n-30) +5615076543224*a(n-31) +596139936244*a(n-32) -2532457629816*a(n-33) -11619231656*a(n-34) +811694638348*a(n-35) -54333866496*a(n-36) -180592320980*a(n-37) +21480028944*a(n-38) +26801997448*a(n-39) -4229090640*a(n-40) -2481395056*a(n-41) +464483232*a(n-42) +126694304*a(n-43) -26501248*a(n-44) -2659968*a(n-45) +599040*a(n-46) for n>47

EXAMPLE

Some solutions for n=3

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

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

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

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

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

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

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

CROSSREFS

Sequence in context: A215960 A279070 A046320 * A255113 A255628 A232287

Adjacent sequences:  A232923 A232924 A232925 * A232927 A232928 A232929

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 02 2013

STATUS

approved

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Last modified December 13 20:06 EST 2018. Contains 318087 sequences. (Running on oeis4.)