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 A209551 1/4 the number of (n+1)X7 0..3 arrays with every 2X2 subblock having exactly two distinct clockwise edge differences 1

%I

%S 1909,90186,3901194,174401424,7751834609,345350598642,15380031974285,

%T 685056630399243,30513075478492148,1359098254767356166,

%U 60536202458667509812,2696372582587335783278,120100441888134027505702

%N 1/4 the number of (n+1)X7 0..3 arrays with every 2X2 subblock having exactly two distinct clockwise edge differences

%C Column 6 of A209553

%H R. H. Hardin, <a href="/A209551/b209551.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 93*a(n-1) -2828*a(n-2) +25792*a(n-3) +371376*a(n-4) -9898959*a(n-5) +50997316*a(n-6) +600219584*a(n-7) -8458938650*a(n-8) +15460753459*a(n-9) +324261513320*a(n-10) -1997445245287*a(n-11) -2888253677269*a(n-12) +61818955362264*a(n-13) -105335609798253*a(n-14) -919549637987857*a(n-15) +3635125259976035*a(n-16) +6249958420274094*a(n-17) -54555499290246451*a(n-18) +11571882298429625*a(n-19) +495953594288336739*a(n-20) -657345762489787062*a(n-21) -2942275874522263687*a(n-22) +6881779713200302370*a(n-23) +11244898913169983370*a(n-24) -42974781730107130109*a(n-25) -23051215421912913536*a(n-26) +185864776798114709968*a(n-27) -12863209686911573111*a(n-28) -587984628431521336548*a(n-29) +276016166528678978015*a(n-30) +1397897524468136739882*a(n-31) -1073664296329817362259*a(n-32) -2537929904791966336740*a(n-33) +2568552806109627886272*a(n-34) +3559706199665273218930*a(n-35) -4354397060651285431293*a(n-36) -3901454743539065189517*a(n-37) +5483143910166447182278*a(n-38) +3391429255331125848034*a(n-39) -5229357377757064837770*a(n-40) -2387498579023401955317*a(n-41) +3802827193424184634130*a(n-42) +1394499277589912306144*a(n-43) -2104672583906607527310*a(n-44) -686223001308051264232*a(n-45) +877657767435453737858*a(n-46) +281766806240431459892*a(n-47) -270362730870675484681*a(n-48) -92957087420024768497*a(n-49) +59494538810619139593*a(n-50) +23369146321510311361*a(n-51) -8826604119797680384*a(n-52) -4236074000925921714*a(n-53) +782901241541277381*a(n-54) +524243697816902673*a(n-55) -26069037492083522*a(n-56) -41764242069671064*a(n-57) -1908566223569902*a(n-58) +1979458374052951*a(n-59) +240266789154528*a(n-60) -47527093603425*a(n-61) -10067754548810*a(n-62) +255750935719*a(n-63) +181717983160*a(n-64) +9192680176*a(n-65) -1053768700*a(n-66) -122161293*a(n-67) -1991984*a(n-68) +258490*a(n-69) +14852*a(n-70) +296*a(n-71) +2*a(n-72)

%e Some solutions for n=4

%e ..2..3..0..3..0..1..0....3..2..1..2..3..2..3....1..2..3..2..1..2..3

%e ..1..0..3..0..3..2..1....0..1..2..3..2..3..2....0..3..2..1..0..1..2

%e ..0..1..2..1..2..3..0....1..2..1..2..1..2..3....1..2..3..2..3..2..3

%e ..3..2..1..0..3..2..1....2..3..0..1..2..3..2....2..1..0..1..0..1..0

%e ..2..1..0..1..2..3..2....3..2..1..2..1..2..3....3..2..3..2..3..2..3

%K nonn

%O 1,1

%A _R. H. Hardin_ Mar 10 2012

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Last modified May 23 00:47 EDT 2022. Contains 353959 sequences. (Running on oeis4.)