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A207487 Number of nX7 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 1 1 and 1 1 0 vertically 1
25, 625, 2141, 6217, 21991, 73325, 268275, 959855, 3607311, 13436035, 51497695, 196706551, 765001527, 2972743953, 11691712763, 46007927815, 182581500547, 725456035227, 2900274648193, 11612610826251, 46711361492143 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A207488

LINKS

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

FORMULA

Empirical: a(n) = 11*a(n-1) +107*a(n-2) -1544*a(n-3) -4665*a(n-4) +103517*a(n-5) +79273*a(n-6) -4417010*a(n-7) +1658228*a(n-8) +134851268*a(n-9) -144073399*a(n-10) -3139949425*a(n-11) +4816952968*a(n-12) +58043514861*a(n-13) -108321260880*a(n-14) -875507971747*a(n-15) +1847918776866*a(n-16) +10991284995935*a(n-17) -25194822715671*a(n-18) -116566373095782*a(n-19) +282697190037697*a(n-20) +1056320971943357*a(n-21) -2660122712965582*a(n-22) -8252517373730467*a(n-23) +21269234145931063*a(n-24) +55973422045200612*a(n-25) -145893053058207816*a(n-26) -331405111314286310*a(n-27) +864729384927746904*a(n-28) +1720114206689379780*a(n-29) -4453298182827579721*a(n-30) -7851740550909801089*a(n-31) +20011524769171261035*a(n-32) +31593273282326617036*a(n-33) -78720182456370185784*a(n-34) -112234705155227484226*a(n-35) +271746144363134379170*a(n-36) +352343923433176349970*a(n-37) -824684132127424004163*a(n-38) -977852669248229560373*a(n-39) +2202862734996103368181*a(n-40) +2398803508421977962304*a(n-41) -5182908259907206732205*a(n-42) -5198651748780382835087*a(n-43) +10743818216060312959648*a(n-44) +9943831500700455556815*a(n-45) -19618701838474280594267*a(n-46) -16765712040199648245222*a(n-47) +31539678429337808938792*a(n-48) +24876468725136692999766*a(n-49) -44595570570753555225604*a(n-50) -32419499846831045687434*a(n-51) +55381690703435499326262*a(n-52) +37024174456710760063276*a(n-53) -60295755756908922594612*a(n-54) -36956333414016193924932*a(n-55) +57419773643285800719508*a(n-56) +32145494204890232181660*a(n-57) -47696267276799637173996*a(n-58) -24283070573711006264000*a(n-59) +34443941623237837966032*a(n-60) +15869246392990622729352*a(n-61) -21539557729844702144208*a(n-62) -8931935002013066062920*a(n-63) +11610107403601091661752*a(n-64) +4307531380234256362992*a(n-65) -5364408240057393401920*a(n-66) -1769149131405411453088*a(n-67) +2110815464120818560496*a(n-68) +614311788827893866976*a(n-69) -701783055280536974496*a(n-70) -178742438734762042592*a(n-71) +195257425837878260480*a(n-72) +43094423323283395072*a(n-73) -44923352520169857664*a(n-74) -8485881487817545600*a(n-75) +8417271850760046336*a(n-76) +1338698386520186880*a(n-77) -1258855095921116160*a(n-78) -164709672978575360*a(n-79) +146180099494096896*a(n-80) +15192169073197056*a(n-81) -12659962837286912*a(n-82) -985913397051392*a(n-83) +767104134807552*a(n-84) +40051760431104*a(n-85) -28927611371520*a(n-86) -764411904000*a(n-87) +509607936000*a(n-88) for n>89

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Sequence in context: A207513 A207687 A207345 * A207268 A208106 A207727

Adjacent sequences:  A207484 A207485 A207486 * A207488 A207489 A207490

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 18 2012

STATUS

approved

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Last modified January 18 00:43 EST 2022. Contains 350410 sequences. (Running on oeis4.)