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A295048
Number of nX5 0..1 arrays with each 1 horizontally or vertically adjacent to 0 or 2 1s.
1
13, 120, 1027, 9045, 79855, 700972, 6171389, 54282231, 477606439, 4201803890, 36967769965, 325237650675, 2861429906335, 25174648217769, 221485132130347, 1948612085315302, 17143771056376892, 150829836716963750
OFFSET
1,1
COMMENTS
Column 5 of A295051.
LINKS
FORMULA
Empirical: a(n) = 8*a(n-1) +18*a(n-2) -81*a(n-3) -142*a(n-4) -95*a(n-5) +1565*a(n-6) -3275*a(n-7) +808*a(n-8) -2079*a(n-9) +24538*a(n-10) -8206*a(n-11) -48843*a(n-12) +77624*a(n-13) -65656*a(n-14) +33241*a(n-15) -41828*a(n-16) -58983*a(n-17) +130068*a(n-18) -357185*a(n-19) +174687*a(n-20) +71134*a(n-21) +126742*a(n-22) +302854*a(n-23) -166029*a(n-24) +168201*a(n-25) +113052*a(n-26) +267168*a(n-27) +57340*a(n-28) -252720*a(n-29) -122396*a(n-30) +5446*a(n-31) +199276*a(n-32) +146220*a(n-33) +32766*a(n-34) -42894*a(n-35) -53195*a(n-36) -15364*a(n-37) -1639*a(n-38) +4531*a(n-39) +1778*a(n-40) +462*a(n-41) +288*a(n-42) -6*a(n-43) +23*a(n-44) -77*a(n-45) +10*a(n-46) -a(n-47) -2*a(n-48) +a(n-49)
EXAMPLE
Some solutions for n=5
..0..0..0..0..0. .1..0..0..0..0. .1..0..1..1..0. .1..0..1..0..1
..1..0..0..0..0. .0..0..0..0..1. .0..0..1..1..0. .0..0..0..1..0
..0..1..0..0..0. .1..0..1..1..0. .1..0..0..0..0. .0..0..1..0..0
..0..0..0..1..1. .0..0..1..1..0. .0..0..1..1..0. .0..0..0..1..0
..1..0..0..1..1. .1..0..0..0..0. .0..0..1..1..0. .0..0..1..0..0
CROSSREFS
Cf. A295051.
Sequence in context: A121086 A159969 A253512 * A295376 A188709 A054962
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 13 2017
STATUS
approved