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A207247 Number of 7Xn 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 0 1 0 vertically 1
31, 961, 6759, 44730, 228110, 886959, 3510185, 11662500, 37779767, 116530737, 339866809, 977292885, 2712629425, 7395159649, 19850488276, 52392219734, 136945372844, 354108951154, 908054491477, 2312990201683, 5853875753478 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 7 of A207242

LINKS

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

FORMULA

Empirical: a(n) = 9*a(n-1) -14*a(n-2) -85*a(n-3) +192*a(n-4) +678*a(n-5) -1545*a(n-6) -4104*a(n-7) +7888*a(n-8) +20558*a(n-9) -28540*a(n-10) -82000*a(n-11) +72331*a(n-12) +254895*a(n-13) -120648*a(n-14) -604025*a(n-15) +115548*a(n-16) +1051198*a(n-17) -76383*a(n-18) -1272428*a(n-19) +388077*a(n-20) +934715*a(n-21) -1739880*a(n-22) -233523*a(n-23) +4213934*a(n-24) -320174*a(n-25) -6378421*a(n-26) +1196510*a(n-27) +6219540*a(n-28) -3865614*a(n-29) -3557222*a(n-30) +8599232*a(n-31) -287910*a(n-32) -12448800*a(n-33) +4398124*a(n-34) +12056358*a(n-35) -8897351*a(n-36) -6867251*a(n-37) +13006318*a(n-38) -1073395*a(n-39) -13992625*a(n-40) +7972395*a(n-41) +10913113*a(n-42) -12317893*a(n-43) -3639719*a(n-44) +12284569*a(n-45) -3572181*a(n-46) -9279867*a(n-47) +8215899*a(n-48) +4076131*a(n-49) -8796607*a(n-50) +1135263*a(n-51) +6038813*a(n-52) -3803927*a(n-53) -2865657*a(n-54) +4663121*a(n-55) -461440*a(n-56) -2889294*a(n-57) +1489847*a(n-58) +1401888*a(n-59) -1856003*a(n-60) +107403*a(n-61) +1109328*a(n-62) -588551*a(n-63) -379669*a(n-64) +489373*a(n-65) +59569*a(n-66) -399537*a(n-67) +249378*a(n-68) +12026*a(n-69) -52973*a(n-70) -63414*a(n-71) +127143*a(n-72) -87619*a(n-73) +27000*a(n-74) -9709*a(n-75) +23348*a(n-76) -29098*a(n-77) +19883*a(n-78) -8480*a(n-79) +3857*a(n-80) -4167*a(n-81) +4018*a(n-82) -2563*a(n-83) +1097*a(n-84) -441*a(n-85) +353*a(n-86) -287*a(n-87) +165*a(n-88) -61*a(n-89) +17*a(n-90) -11*a(n-91) +8*a(n-92) -4*a(n-93) +a(n-94)

EXAMPLE

Some solutions for n=4

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

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

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

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

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

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

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

CROSSREFS

Sequence in context: A207518 A207067 A207122 * A208168 A207441 A207431

Adjacent sequences:  A207244 A207245 A207246 * A207248 A207249 A207250

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 16 2012

STATUS

approved

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Last modified September 23 20:42 EDT 2021. Contains 347617 sequences. (Running on oeis4.)