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A207127 Number of 7Xn 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 0 1 and 0 1 1 vertically 1
20, 400, 2340, 13200, 87744, 475984, 2330037, 11635558, 55554808, 251535759, 1124853720, 4944356292, 21187341735, 89511994640, 374050079444, 1542084294888, 6290403091560, 25452983767264, 102144395660496 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 7 of A207123

LINKS

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

FORMULA

Empirical: a(n) = 14*a(n-1) -85*a(n-2) +465*a(n-3) -2822*a(n-4) +12754*a(n-5) -49933*a(n-6) +221157*a(n-7) -822163*a(n-8) +2623048*a(n-9) -9629962*a(n-10) +30940490*a(n-11) -83877127*a(n-12) +271445106*a(n-13) -776325841*a(n-14) +1815714481*a(n-15) -5411660781*a(n-16) +14035468772*a(n-17) -28313347286*a(n-18) +81087340968*a(n-19) -192557799542*a(n-20) +330145401354*a(n-21) -956433942970*a(n-22) +2077668559612*a(n-23) -2930469039412*a(n-24) +9220909157736*a(n-25) -18049249228634*a(n-26) +19708041889332*a(n-27) -74973728810243*a(n-28) +127836810352284*a(n-29) -95798677241303*a(n-30) +527014304509161*a(n-31) -739141589649874*a(n-32) +274155640271866*a(n-33) -3254553426680445*a(n-34) +3442351405160113*a(n-35) +251735582682661*a(n-36) +17755326582683868*a(n-37) -12397164148419178*a(n-38) -8416874103601210*a(n-39) -85238813721035527*a(n-40) +30462323265391834*a(n-41) +57394192756314261*a(n-42) +356641326189364413*a(n-43) -21154865730496055*a(n-44) -255789417360060438*a(n-45) -1285870672369593082*a(n-46) -239393332410432412*a(n-47) +850275238654182400*a(n-48) +3953493496920048448*a(n-49) +1502759028308998816*a(n-50) -2190587059135330320*a(n-51) -10273265200251020496*a(n-52) -5429085403228467040*a(n-53) +4418865045976514272*a(n-54) +22389152106247372416*a(n-55) +14282822084351523904*a(n-56) -6954042835118706560*a(n-57) -40627618659809065600*a(n-58) -29001696212110566912*a(n-59) +8426293314130777856*a(n-60) +60910606360484891136*a(n-61) +46263593091806492160*a(n-62) -7710740741859591168*a(n-63) -74747053931918579712*a(n-64) -58035913196236812288*a(n-65) +5271114170652475392*a(n-66) +74155386899211190272*a(n-67) +56696829452796100608*a(n-68) -2887939270111002624*a(n-69) -58437094989686243328*a(n-70) -42268173079509467136*a(n-71) +1706149960629092352*a(n-72) +35632041588440432640*a(n-73) +23235629071699279872*a(n-74) -1288493772501417984*a(n-75) -16132821706296262656*a(n-76) -8894278787747807232*a(n-77) +842463838702927872*a(n-78) +5068707999762087936*a(n-79) +2129759193740083200*a(n-80) -340333498176897024*a(n-81) -973115091056590848*a(n-82) -248794866908135424*a(n-83) +68475651442606080*a(n-84) +82170781731127296*a(n-85)

EXAMPLE

Some solutions for n=4

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

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

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

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

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

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

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

CROSSREFS

Sequence in context: A267718 A207402 A207751 * A207948 A206938 A208141

Adjacent sequences:  A207124 A207125 A207126 * A207128 A207129 A207130

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 15 2012

STATUS

approved

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Last modified May 28 18:24 EDT 2022. Contains 354122 sequences. (Running on oeis4.)