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A206507
Number of (n+1) X 4 0..2 arrays with the number of clockwise edge increases in 2 X 2 subblocks nondecreasing rightwards and downwards.
1
3399, 93405, 2105607, 41873838, 769739571, 13397007426, 224125465767, 3639506017737, 57759037910145, 900227925756975, 13830131604178527, 210015057307677960, 3159110458844182341, 47153204170712651499
OFFSET
1,1
COMMENTS
Column 3 of A206512.
LINKS
FORMULA
Empirical: a(n) = 43*a(n-1) -560*a(n-2) -301*a(n-3) +58140*a(n-4) -266678*a(n-5) -2052111*a(n-6) +15616295*a(n-7) +32553554*a(n-8) -428019493*a(n-9) -140101975*a(n-10) +7157244486*a(n-11) -3878496130*a(n-12) -81350820700*a(n-13) +92282193531*a(n-14) +661037913951*a(n-15) -1153139822216*a(n-16) -3750375673397*a(n-17) +10272007050117*a(n-18) +11307559698334*a(n-19) -66861682621412*a(n-20) +30396309007373*a(n-21) +286797532029361*a(n-22) -577253429355795*a(n-23) -515274276475600*a(n-24) +3288213731014612*a(n-25) -2319778381651637*a(n-26) -9210618806887255*a(n-27) +21522479749004936*a(n-28) +386994035523308*a(n-29) -84485292746124261*a(n-30) +120213656794023933*a(n-31) +200479767563622238*a(n-32) -651342756788935634*a(n-33) -218995076753278783*a(n-34) +2240168025280749856*a(n-35) -562599124935184162*a(n-36) -5718074917398148106*a(n-37) +3896739065818876813*a(n-38) +11157819107569565092*a(n-39) -12344609689373548452*a(n-40) -16519275709140140613*a(n-41) +27575879497435303388*a(n-42) +17037875789330156165*a(n-43) -47145213836213708945*a(n-44) -7362526243707437385*a(n-45) +61857433515558819146*a(n-46) -12108244633773880734*a(n-47) -59603119051405911044*a(n-48) +29684960133920835544*a(n-49) +38742581976811825635*a(n-50) -30923987787997544536*a(n-51) -14971734351034264399*a(n-52) +17593615001634785102*a(n-53) +3693415397812903566*a(n-54) -5865717176480173312*a(n-55) -2285287018681816803*a(n-56) +3279660163779884229*a(n-57) +1117819441930804736*a(n-58) -3810709135189499181*a(n-59) +1209355289383345147*a(n-60) +2609574092234205911*a(n-61) -2025943866398526978*a(n-62) -748404131952133991*a(n-63) +1374111095557955776*a(n-64) -254509843997104061*a(n-65) -529334312705599289*a(n-66) +396629471902305293*a(n-67) +58155671568981384*a(n-68) -197049151694905447*a(n-69) +56626096310808263*a(n-70) +40736308817253334*a(n-71) -33420664239714004*a(n-72) +3623368762119517*a(n-73) +9036297022738612*a(n-74) -4794775820304365*a(n-75) -1345199351985969*a(n-76) +1724273351995858*a(n-77) -167082321416272*a(n-78) -345131182064849*a(n-79) +193604547939728*a(n-80) -1504243529745*a(n-81) -48820505858969*a(n-82) +17081169883351*a(n-83) +2777154345220*a(n-84) -2638202409776*a(n-85) +598690007258*a(n-86) -61405109728*a(n-87) -59373700630*a(n-88) +37856079048*a(n-89) -5347077919*a(n-90) -1361201971*a(n-91) +736710444*a(n-92) -144960710*a(n-93) -4344552*a(n-94) +7376088*a(n-95) -1422720*a(n-96) +99840*a(n-97).
EXAMPLE
Some solutions for n=4
..1..0..1..2....1..1..1..1....1..1..1..2....1..2..0..0....0..1..2..1
..2..1..0..1....1..0..0..0....1..2..2..2....2..0..2..1....0..0..0..2
..1..0..1..2....1..2..2..2....1..1..2..0....2..1..0..2....2..2..1..0
..0..1..0..0....1..1..2..1....1..2..0..1....0..2..1..0....1..1..2..1
..1..0..2..1....0..2..0..2....1..2..1..2....1..0..2..1....1..2..0..2
CROSSREFS
Cf. A206512.
Sequence in context: A185926 A221009 A226667 * A133532 A224744 A151772
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 08 2012
STATUS
approved