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A207504 Number of 7Xn 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 1 0 0 vertically 1
35, 1225, 9723, 62530, 343310, 1413961, 5715255, 20090516, 67370124, 216796950, 667696708, 2029712814, 6055036914, 17929790545, 52996398729, 156389908011, 463168251873, 1376399848038, 4108298709116, 12322769960737, 37117215785687 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 7 of A207500

LINKS

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

FORMULA

Empirical: a(n) = 7*a(n-1) -87*a(n-3) +44*a(n-4) +696*a(n-5) -395*a(n-6) -3907*a(n-7) +2044*a(n-8) +15727*a(n-9) -6955*a(n-10) -47163*a(n-11) +19943*a(n-12) +103304*a(n-13) -56805*a(n-14) -156350*a(n-15) +165115*a(n-16) +126712*a(n-17) -436222*a(n-18) +93943*a(n-19) +928117*a(n-20) -562039*a(n-21) -1519131*a(n-22) +1248418*a(n-23) +1814478*a(n-24) -2052689*a(n-25) -1321996*a(n-26) +2792544*a(n-27) -99622*a(n-28) -3210970*a(n-29) +2020784*a(n-30) +2910382*a(n-31) -3568700*a(n-32) -1678972*a(n-33) +4068898*a(n-34) -170210*a(n-35) -3413616*a(n-36) +1845998*a(n-37) +1925622*a(n-38) -2549098*a(n-39) -296726*a(n-40) +2195840*a(n-41) -872982*a(n-42) -1206724*a(n-43) +1249822*a(n-44) +209580*a(n-45) -949808*a(n-46) +352042*a(n-47) +415322*a(n-48) -475266*a(n-49) +21562*a(n-50) +305476*a(n-51) -177704*a(n-52) -90830*a(n-53) +145908*a(n-54) -38912*a(n-55) -62601*a(n-56) +69611*a(n-57) -2808*a(n-58) -38287*a(n-59) +19248*a(n-60) +9708*a(n-61) -16247*a(n-62) +5653*a(n-63) +6236*a(n-64) -5957*a(n-65) -371*a(n-66) +2501*a(n-67) -1209*a(n-68) -616*a(n-69) +939*a(n-70) -150*a(n-71) -209*a(n-72) +148*a(n-73) +14*a(n-74) -73*a(n-75) +17*a(n-76) +9*a(n-77) -7*a(n-78) +2*a(n-79) +2*a(n-80) -a(n-81)

EXAMPLE

Some solutions for n=4

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

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

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

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

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

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

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

CROSSREFS

Sequence in context: A207756 A207937 A208697 * A207965 A207447 A207745

Adjacent sequences:  A207501 A207502 A207503 * A207505 A207506 A207507

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 18 2012

STATUS

approved

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Last modified October 23 04:06 EDT 2021. Contains 348211 sequences. (Running on oeis4.)