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A207274 Number of 7Xn 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 1 1 and 1 0 1 vertically 1
31, 961, 2305, 13067, 52240, 135686, 467686, 1233127, 3284096, 8655283, 21076355, 52058229, 123345376, 288255238, 665907876, 1506716940, 3386544920, 7505699199, 16482389432, 35903584588, 77477997261, 166138926351, 353659351084 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 7 of A207269

LINKS

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

FORMULA

Empirical: a(n) = 3*a(n-1) +11*a(n-2) -8*a(n-3) -143*a(n-4) -76*a(n-5) +751*a(n-6) +1772*a(n-7) -1861*a(n-8) -10580*a(n-9) -8585*a(n-10) +32732*a(n-11) +75951*a(n-12) +2648*a(n-13) -253547*a(n-14) -356014*a(n-15) +188511*a(n-16) +1272512*a(n-17) +1267179*a(n-18) -1196288*a(n-19) -4765018*a(n-20) -3880833*a(n-21) +4317310*a(n-22) +14348194*a(n-23) +11074548*a(n-24) -10710970*a(n-25) -36029644*a(n-26) -29610976*a(n-27) +18315787*a(n-28) +76111765*a(n-29) +71261505*a(n-30) -16610670*a(n-31) -133926626*a(n-32) -148292571*a(n-33) -16031238*a(n-34) +191296892*a(n-35) +259865173*a(n-36) +103256591*a(n-37) -209843953*a(n-38) -376102248*a(n-39) -247062694*a(n-40) +149654929*a(n-41) +439488782*a(n-42) +406599492*a(n-43) -5212254*a(n-44) -397709768*a(n-45) -508447090*a(n-46) -172897780*a(n-47) +249245184*a(n-48) +494388226*a(n-49) +302144236*a(n-50) -56655544*a(n-51) -368743392*a(n-52) -326339892*a(n-53) -94189340*a(n-54) +197251436*a(n-55) +254729393*a(n-56) +154258069*a(n-57) -56447543*a(n-58) -145507468*a(n-59) -135279611*a(n-60) -16778638*a(n-61) +55810039*a(n-62) +83293640*a(n-63) +33077757*a(n-64) -8033002*a(n-65) -37534699*a(n-66) -23213060*a(n-67) -6645777*a(n-68) +11898622*a(n-69) +10538341*a(n-70) +6315786*a(n-71) -2138585*a(n-72) -3258664*a(n-73) -3079337*a(n-74) -141268*a(n-75) +604050*a(n-76) +1030647*a(n-77) +245910*a(n-78) -7602*a(n-79) -249492*a(n-80) -90498*a(n-81) -36112*a(n-82) +43404*a(n-83) +19773*a(n-84) +13107*a(n-85) -5181*a(n-86) -2766*a(n-87) -2660*a(n-88) +381*a(n-89) +232*a(n-90) +344*a(n-91) -13*a(n-92) -9*a(n-93) -27*a(n-94) +a(n-97) for n>99

EXAMPLE

Some solutions for n=4

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

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

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

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

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

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

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

CROSSREFS

Sequence in context: A171336 A200442 A207777 * A207767 A207734 A208693

Adjacent sequences:  A207271 A207272 A207273 * A207275 A207276 A207277

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 16 2012

STATUS

approved

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Last modified August 3 01:07 EDT 2021. Contains 346429 sequences. (Running on oeis4.)