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A240652 Number of nX4 0..1 arrays with no element equal to exactly one horizontal or vertical neighbor, with new values 0..1 introduced in row major order 1
1, 3, 17, 91, 352, 1545, 7154, 33269, 154974, 724237, 3394852, 15935126, 74854028, 351802659, 1653966146, 7777530146, 36577083726, 172031838421, 809149353515, 3805931188358, 17901967673107, 84206433807963, 396088887787212 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 4 of A240656

LINKS

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

FORMULA

Empirical: a(n) = 6*a(n-1) -5*a(n-2) +2*a(n-3) -17*a(n-4) -64*a(n-5) -92*a(n-6) +24*a(n-7) +159*a(n-8) +803*a(n-9) +1491*a(n-10) +1970*a(n-11) +1678*a(n-12) -661*a(n-13) -5546*a(n-14) -11953*a(n-15) -18840*a(n-16) -20162*a(n-17) -13954*a(n-18) +3124*a(n-19) +29982*a(n-20) +57408*a(n-21) +71870*a(n-22) +67778*a(n-23) +36825*a(n-24) -12790*a(n-25) -63687*a(n-26) -92941*a(n-27) -91422*a(n-28) -61244*a(n-29) -12245*a(n-30) +25219*a(n-31) +41068*a(n-32) +34422*a(n-33) +19986*a(n-34) +4392*a(n-35) -450*a(n-36) +906*a(n-37) +3453*a(n-38) +4580*a(n-39) +4351*a(n-40) +1645*a(n-41) -1495*a(n-42) -2735*a(n-43) -2047*a(n-44) -913*a(n-45) -160*a(n-46) +116*a(n-47) +114*a(n-48) +44*a(n-49) +8*a(n-50)

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Sequence in context: A037794 A203851 A198766 * A204092 A221731 A290925

Adjacent sequences:  A240649 A240650 A240651 * A240653 A240654 A240655

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 09 2014

STATUS

approved

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Last modified May 15 16:02 EDT 2021. Contains 343920 sequences. (Running on oeis4.)