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A268739 Number of nX7 binary arrays with some 1 horizontally or vertically adjacent to some other 1 exactly once. 1
38, 1183, 33170, 816009, 18847982, 418632185, 9039552112, 191307160577, 3985770068310, 82030747371058, 1671509767296774, 33781019022038039, 678004335124666334, 13528033902348727292, 268553181861956273470 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A268740.

LINKS

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

FORMULA

Empirical: a(n) = 18*a(n-1) +325*a(n-2) -4074*a(n-3) -48747*a(n-4) +201072*a(n-5) +2225020*a(n-6) -6248320*a(n-7) -47573325*a(n-8) +135873052*a(n-9) +512366407*a(n-10) -1794441336*a(n-11) -2517416282*a(n-12) +13453431136*a(n-13) +1270823811*a(n-14) -55187301646*a(n-15) +38695555999*a(n-16) +115237077158*a(n-17) -158181613013*a(n-18) -96178246900*a(n-19) +263575852534*a(n-20) -18739881048*a(n-21) -224653932202*a(n-22) +90835575680*a(n-23) +105290165907*a(n-24) -69076575582*a(n-25) -27720217521*a(n-26) +26811874806*a(n-27) +3877126783*a(n-28) -6197138172*a(n-29) -207452034*a(n-30) +895782500*a(n-31) -10034133*a(n-32) -81777708*a(n-33) +1520627*a(n-34) +4630616*a(n-35) -28132*a(n-36) -153828*a(n-37) -2195*a(n-38) +2658*a(n-39) +93*a(n-40) -18*a(n-41) -a(n-42)

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Cf. A268740.

Sequence in context: A208949 A255496 A098612 * A239043 A137030 A027657

Adjacent sequences:  A268736 A268737 A268738 * A268740 A268741 A268742

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 12 2016

STATUS

approved

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Last modified February 21 06:25 EST 2018. Contains 299390 sequences. (Running on oeis4.)