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A207921 Number of 6Xn 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 1 0 and 1 0 1 vertically 1
26, 676, 3910, 23637, 117835, 612439, 3327954, 17621905, 92785236, 493226298, 2618710999, 13869205695, 73534808659, 390043559718, 2067950383577, 10964045099346, 58137529835416, 308266004747279, 1634495531671201 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 6 of A207918

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +7*a(n-2) +84*a(n-3) +162*a(n-4) -211*a(n-5) -2539*a(n-6) -6869*a(n-7) -1500*a(n-8) +43337*a(n-9) +118112*a(n-10) +64060*a(n-11) -388208*a(n-12) -1086391*a(n-13) -826341*a(n-14) +1897949*a(n-15) +5944507*a(n-16) +5846146*a(n-17) -4239578*a(n-18) -20302409*a(n-19) -24744608*a(n-20) -416618*a(n-21) +41293114*a(n-22) +62640453*a(n-23) +25458037*a(n-24) -47567000*a(n-25) -93157981*a(n-26) -52063069*a(n-27) +28324666*a(n-28) +87341962*a(n-29) +30300393*a(n-30) -22313684*a(n-31) -74160954*a(n-32) +31894815*a(n-33) +32122983*a(n-34) +107210353*a(n-35) -88336649*a(n-36) +6535109*a(n-37) -157060363*a(n-38) +124419889*a(n-39) -85357841*a(n-40) +161199662*a(n-41) -144742778*a(n-42) +120357887*a(n-43) -117132939*a(n-44) +122521503*a(n-45) -82460666*a(n-46) +59827267*a(n-47) -66607410*a(n-48) +31225295*a(n-49) -22660395*a(n-50) +22092687*a(n-51) -6699063*a(n-52) +6991080*a(n-53) -3497192*a(n-54) +942478*a(n-55) -1619789*a(n-56) -288168*a(n-57) -224812*a(n-58) +139695*a(n-59) +220677*a(n-60) +47594*a(n-61) +49190*a(n-62) -26558*a(n-63) +4246*a(n-64) -12332*a(n-65) -1512*a(n-66) -2071*a(n-67) +147*a(n-68) +176*a(n-69) +170*a(n-70) +32*a(n-71) +14*a(n-72) +14*a(n-73) -6*a(n-74) for n>76

EXAMPLE

Some solutions for n=4

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

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

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

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

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

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

CROSSREFS

Sequence in context: A207451 A208553 A262271 * A208701 A207470 A207522

Adjacent sequences:  A207918 A207919 A207920 * A207922 A207923 A207924

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 21 2012

STATUS

approved

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Last modified September 28 21:22 EDT 2021. Contains 347717 sequences. (Running on oeis4.)