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5X5X5 triangular graph without horizontal edges coloring a rectangular array: number of nX4 0..14 arrays where 0..14 label nodes of a graph with edges 0,1 0,2 1,3 1,4 2,4 2,5 3,6 3,7 4,7 4,8 5,8 5,9 6,10 6,11 7,11 7,12 8,12 8,13 9,13 9,14 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph
1

%I #4 Mar 20 2013 05:46:06

%S 356,11168,394736,14270468,522011152,19187276496,707293805988,

%T 26110271476744,964706306602248,35659725052665944,1318493647550197552,

%U 48757719264021531560,1803213225574814956884,66691851687923955861152

%N 5X5X5 triangular graph without horizontal edges coloring a rectangular array: number of nX4 0..14 arrays where 0..14 label nodes of a graph with edges 0,1 0,2 1,3 1,4 2,4 2,5 3,6 3,7 4,7 4,8 5,8 5,9 6,10 6,11 7,11 7,12 8,12 8,13 9,13 9,14 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph

%C Column 4 of A223432

%H R. H. Hardin, <a href="/A223428/b223428.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 90*a(n-1) -2382*a(n-2) -5851*a(n-3) +1185032*a(n-4) -12751424*a(n-5) -147375985*a(n-6) +3273708212*a(n-7) -1168111789*a(n-8) -323647444388*a(n-9) +1437779069985*a(n-10) +16186927709385*a(n-11) -125242315912444*a(n-12) -413235224470677*a(n-13) +5636480667293840*a(n-14) +2675663283401746*a(n-15) -159026686066589326*a(n-16) +166509342016432039*a(n-17) +3028188310899621548*a(n-18) -6383129956393481851*a(n-19) -40277954027537811627*a(n-20) +122930347681762016808*a(n-21) +377848121308445104815*a(n-22) -1567942435557566705597*a(n-23) -2446348750208859246237*a(n-24) +14376673054018669801356*a(n-25) +9834205763847336386085*a(n-26) -98491136965829011054574*a(n-27) -11032841879864789986393*a(n-28) +515409955861972526740139*a(n-29) -151400819078918167199246*a(n-30) -2089269980813555081335146*a(n-31) +1257505625483438262653038*a(n-32) +6620817862675782715137184*a(n-33) -5638216059009855079193532*a(n-34) -16500225411520187526719329*a(n-35) +17626543895239420982950725*a(n-36) +32450784819120629254505749*a(n-37) -41241621786856615498194847*a(n-38) -50421557691936506753151235*a(n-39) +74445070527604651709548109*a(n-40) +61811653102978472165389882*a(n-41) -105303828568329573268018356*a(n-42) -59508367840589483370664765*a(n-43) +117713417867557052980768776*a(n-44) +44562972029754054220967816*a(n-45) -104417665868649446207199712*a(n-46) -25481130170512244991378397*a(n-47) +73574004478869022860911870*a(n-48) +10707490652787164689705930*a(n-49) -41111391445133892464690283*a(n-50) -2996529497348401711568856*a(n-51) +18140775177847581398098800*a(n-52) +348984267320486319762240*a(n-53) -6277165317584306574534073*a(n-54) +127020749264277083241411*a(n-55) +1685784546683990004024199*a(n-56) -82689627089498738802445*a(n-57) -346279469716458171918497*a(n-58) +24199479663388592510755*a(n-59) +53297563974949750292352*a(n-60) -4522291938509550140432*a(n-61) -5968291960645494882434*a(n-62) +571087613336425857431*a(n-63) +465349417827379918292*a(n-64) -48336072855407563696*a(n-65) -23548583170925441556*a(n-66) +2606296798017051248*a(n-67) +680557811695605000*a(n-68) -79783533495300384*a(n-69) -8271041468576256*a(n-70) +1029784826898432*a(n-71)

%e Some solutions for n=3

%e .11..7.12..8....7..4..1..0....0..1..4..8....7.12..8.13....0..2..4..2

%e ..7.11..7..4....4..1..3..1....2..4..1..4....4..8.13..8....2..0..2..5

%e ..3..7..4..7....1..3..7..4....0..1..4..8....8.13..8..5....0..1..0..2

%K nonn

%O 1,1

%A _R. H. Hardin_ Mar 20 2013