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%I #5 Mar 31 2012 12:36:58
%S 76527504,111152892816,161444773912464,235282648691687184,
%T 343078794839144051856,500356074758382054639504,
%U 729769248139791415275682704,1064383572650821297366532768784
%N Number of (n+1)X8 0..3 arrays with no 2X2 subblock having equal diagonal elements or equal antidiagonal elements
%C Column 7 of A203826
%H R. H. Hardin, <a href="/A203825/b203825.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 1872*a(n-1) -476775*a(n-2) -239359469*a(n-3) +76800472425*a(n-4) +7695363047205*a(n-5) -3436884677106841*a(n-6) -22469569407072375*a(n-7) +61201515041913170232*a(n-8) -1953117939283109264673*a(n-9) -472953064898860367893512*a(n-10) +25508766307849829391801120*a(n-11) +1678096808289539185984789633*a(n-12) -130958281040896084483301695668*a(n-13) -2425634991533220186330341942001*a(n-14) +347148307119218509545564057772141*a(n-15) -906051870076745273455272788159217*a(n-16) -514972579445433456878307389421126129*a(n-17) +8030246906337093617065920920559709561*a(n-18) +422935386813913429126520796309119443995*a(n-19) -11638486387475238539358884811295168607760*a(n-20) -161804897162475199397965908217422249883455*a(n-21) +8196314271560066792221112556620856814259808*a(n-22) -5393272441628047012749192511171884197613348*a(n-23) -3004843723718830257847606762292175902679784448*a(n-24) +27563912971152565008457117057814521505677788912*a(n-25) +496530104202603657391551997690219738476892517376*a(n-26) -9016085181669678845779741765687356518422603682688*a(n-27) -7000453568988401436949090531566970808300136170496*a(n-28) +1024393186562487081832448605154132858476234646904576*a(n-29) -5791792747011995377351726214510585257140743092494336*a(n-30) -20091770773764372286666951368233455995427325862773760*a(n-31) +239834710687460737398214364654402042215293538551103488*a(n-32) -83860654798522224229686795059236746306947999432044544*a(n-33) -3626594286196136019202444152037445294859544445756964864*a(n-34) +4861130795986665769737964659042237349338634022873923584*a(n-35) +26507484380021687330996748172101602177919473805315276800*a(n-36) -43885364448168719858497400079966474956168312874058383360*a(n-37) -99625396669303606792124161488975190503019566419964592128*a(n-38) +164603752491019453264295455980626375155044995166587846656*a(n-39) +180095632344789678757144527778685526143773873988230447104*a(n-40) -262068363479480658640746195237040084599055548332868894720*a(n-41) -109839119596654910382806306565990699616081151471948660736*a(n-42) +131226920917527534866587967575593280796507543188405223424*a(n-43) -30107934215818730670430953297833610862645742146506719232*a(n-44) +1977433226539489389764418814233186807096779914791092224*a(n-45)
%e Some solutions for n=4
%e ..1..0..0..3..2..1..2..3....0..1..0..2..0..1..1..1....0..2..0..3..1..1..2..0
%e ..3..3..1..1..2..1..0..3....2..2..3..1..3..3..0..0....3..1..0..3..2..3..2..1
%e ..0..2..2..3..3..1..0..1....3..1..3..0..2..1..2..1....2..2..0..3..0..0..2..3
%e ..1..3..0..0..0..2..0..3....3..0..2..0..3..0..2..3....1..1..0..1..1..1..1..0
%e ..2..2..1..3..1..1..0..1....2..0..3..0..2..0..1..0....2..2..2..2..2..0..2..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 06 2012