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A207499 Number of nX7 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 1 0 0 vertically 1
25, 625, 3355, 17911, 122061, 804887, 5715255, 40046975, 287772089, 2061595205, 14914823863, 107929360177, 784430935831, 5706698690103, 41607085900821, 303627706072811, 2218432129234439, 16220034510311323, 118680071632234053 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A207500

LINKS

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

FORMULA

Empirical: a(n) = 18*a(n-1) +66*a(n-2) -2802*a(n-3) +3287*a(n-4) +202549*a(n-5) -594991*a(n-6) -9055565*a(n-7) +35807273*a(n-8) +281451314*a(n-9) -1320129061*a(n-10) -6483410366*a(n-11) +34378295343*a(n-12) +115302984880*a(n-13) -675141428095*a(n-14) -1629405069373*a(n-15) +10389151242309*a(n-16) +18705409385974*a(n-17) -128489348784529*a(n-18) -177653284835477*a(n-19) +1300561971191097*a(n-20) +1418377161511435*a(n-21) -10921178734784581*a(n-22) -9659482030287946*a(n-23) +76884075139291826*a(n-24) +56864499202570688*a(n-25) -457523374287874637*a(n-26) -292738188220855624*a(n-27) +2316547347584759449*a(n-28) +1329698182980001754*a(n-29) -10031643449844807108*a(n-30) -5358499084703527109*a(n-31) +37305440507234708547*a(n-32) +19191788243038652032*a(n-33) -119507141792729578909*a(n-34) -61004748090717877126*a(n-35) +330542045644618983443*a(n-36) +171514255554503017904*a(n-37) -790555627453888472557*a(n-38) -424694257955726097233*a(n-39) +1636313719658464847167*a(n-40) +922276764631174671962*a(n-41) -2931482918705846597209*a(n-42) -1749973778066924516735*a(n-43) +4543081947395214311895*a(n-44) +2892077285933850390399*a(n-45) -6082565085480842374095*a(n-46) -4151601341296454973514*a(n-47) +7020283556993245762117*a(n-48) +5163903621874878951386*a(n-49) -6962383319638011984497*a(n-50) -5551898403462398723696*a(n-51) +5906114391425654252428*a(n-52) +5146029295554634179985*a(n-53) -4257361213211101866675*a(n-54) -4099869656946550208362*a(n-55) +2582882796867857620436*a(n-56) +2797545905553856341380*a(n-57) -1299373096888677424682*a(n-58) -1627714050424538188568*a(n-59) +528436596879221754104*a(n-60) +803112362678893069316*a(n-61) -165043370977918807016*a(n-62) -333681250653817943240*a(n-63) +34313150485545919488*a(n-64) +115698836207328981632*a(n-65) -1504826595165613472*a(n-66) -33084418395467674240*a(n-67) -2226873263136821120*a(n-68) +7678289296799728192*a(n-69) +1087035298079278464*a(n-70) -1414038914443296384*a(n-71) -302800702032212992*a(n-72) +199754693346320896*a(n-73) +58359939872584704*a(n-74) -20448913579277312*a(n-75) -8011548881842176*a(n-76) +1347946367512576*a(n-77) +766056924463104*a(n-78) -37397454372864*a(n-79) -47805058990080*a(n-80) -1641961193472*a(n-81) +1695876120576*a(n-82) +158346510336*a(n-83) -24100208640*a(n-84) -3185049600*a(n-85) for n>86

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Sequence in context: A207023 A208116 A207367 * A207241 A207110 A207466

Adjacent sequences:  A207496 A207497 A207498 * A207500 A207501 A207502

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 18 2012

STATUS

approved

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Last modified December 5 10:11 EST 2021. Contains 349543 sequences. (Running on oeis4.)