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 A206571 Number of nX2 0..3 arrays avoiding the pattern z-1 z-1 z in any row, column or nw-to-se diagonal 4
 16, 256, 3721, 53824, 777924, 11242609, 162486009, 2348371600, 33940324441, 490529342884, 7089470711236, 102461949277801, 1480851163185241, 21402288176353681, 309320714104227225, 4470517516089946896 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Column 2 of A206577 LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 16*a(n-1) -12*a(n-2) -166*a(n-3) +134*a(n-4) +1595*a(n-5) -1291*a(n-6) -11538*a(n-7) +9401*a(n-8) +344*a(n-9) -2098*a(n-10) +2832*a(n-11) -1207*a(n-12) -846*a(n-13) +548*a(n-14) +637*a(n-15) -488*a(n-16) +102*a(n-17) -13*a(n-18) -161*a(n-19) +85*a(n-20) +20*a(n-21) -14*a(n-22) -4*a(n-23) +6*a(n-24) -4*a(n-25) +a(n-26) +2*a(n-27) -a(n-28) EXAMPLE Some solutions for n=4 ..2..2....1..3....1..0....2..0....0..0....0..2....3..1....2..3....3..3....1..0 ..1..0....0..1....2..3....1..0....3..0....1..1....1..2....3..0....0..1....1..3 ..0..3....0..0....2..1....2..0....1..2....3..1....0..1....1..2....0..0....1..3 ..0..0....2..0....1..0....1..2....2..0....0..0....0..0....3..2....3..2....3..1 CROSSREFS Sequence in context: A294329 A267929 A122609 * A206791 A221665 A227592 Adjacent sequences:  A206568 A206569 A206570 * A206572 A206573 A206574 KEYWORD nonn AUTHOR R. H. Hardin Feb 09 2012 STATUS approved

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Last modified November 29 21:32 EST 2021. Contains 349416 sequences. (Running on oeis4.)