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A207740 Number of nX7 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 1 and 1 0 0 vertically 1
40, 1600, 20550, 327075, 5959350, 113534330, 2215586241, 43590708750, 861389821740, 17048067532895, 337683209581900, 6690732833251660, 132588872475506025, 2627640756847273700, 52076089665529539750 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A207741

LINKS

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

FORMULA

Empirical: a(n) = 32*a(n-1) -74*a(n-2) -5681*a(n-3) +36864*a(n-4) +379616*a(n-5) -3347394*a(n-6) -12764584*a(n-7) +148257198*a(n-8) +243956822*a(n-9) -3971669976*a(n-10) -2702550914*a(n-11) +71137025286*a(n-12) +14429838852*a(n-13) -901839561612*a(n-14) +34210546254*a(n-15) +8384954113963*a(n-16) -1284041429092*a(n-17) -58527272538120*a(n-18) +11728012112339*a(n-19) +311652839928564*a(n-20) -66235506274270*a(n-21) -1280749779000102*a(n-22) +267753041542212*a(n-23) +4098072327114980*a(n-24) -824906375480790*a(n-25) -10282688460625516*a(n-26) +2006945718348092*a(n-27) +20350191628061686*a(n-28) -3931453373643736*a(n-29) -31912328722759350*a(n-30) +6246115144236038*a(n-31) +39785076954556856*a(n-32) -8041469012168886*a(n-33) -39511371747893882*a(n-34) +8349334794212592*a(n-35) +31278208717969682*a(n-36) -6951475961437730*a(n-37) -19722109387644368*a(n-38) +4616459206223570*a(n-39) +9883326934842532*a(n-40) -2433800045758944*a(n-41) -3921613646635774*a(n-42) +1013855557594116*a(n-43) +1225356648569932*a(n-44) -331967762868842*a(n-45) -299264224053538*a(n-46) +84878286390780*a(n-47) +56566411518117*a(n-48) -16802393821234*a(n-49) -8169166554058*a(n-50) +2546494699357*a(n-51) +886299569042*a(n-52) -291138166440*a(n-53) -70640787008*a(n-54) +24626038986*a(n-55) +4013666266*a(n-56) -1501723992*a(n-57) -156022566*a(n-58) +63735634*a(n-59) +3920928*a(n-60) -1790714*a(n-61) -59044*a(n-62) +30840*a(n-63) +489*a(n-64) -284*a(n-65) -2*a(n-66) +a(n-67) for n>68

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Sequence in context: A208038 A207857 A207425 * A208082 A009984 A041761

Adjacent sequences:  A207737 A207738 A207739 * A207741 A207742 A207743

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 19 2012

STATUS

approved

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Last modified July 31 01:50 EDT 2021. Contains 346365 sequences. (Running on oeis4.)