cp's OEIS Frontend

A198524 Number of nX4 0..4 arrays with values 0..4 introduced in row major order and each element equal to no more than two horizontal and vertical neighbors.

%I A198524 #7 Jul 22 2025 12:59:19
%S A198524 15,3660,1877316,1084539825,634586561196,371815743708461,
%T A198524 217885196778717007,127683385189755792564,74824145653256981522691,
%U A198524 43847942678019724723096730,25695476991145191912238756667
%N A198524 Number of nX4 0..4 arrays with values 0..4 introduced in row major order and each element equal to no more than two horizontal and vertical neighbors.
%C A198524 Column 4 of A198528
%H A198524 R. H. Hardin, <a href="/A198524/b198524.txt">Table of n, a(n) for n = 1..202</a>
%F A198524 Empirical: a(n) = 635*a(n-1) -27578*a(n-2) -664895*a(n-3) +1075136*a(n-4) +521286483*a(n-5) +2748227094*a(n-6) -89204651105*a(n-7) -1168115845047*a(n-8) +9306591915990*a(n-9) +42304788343962*a(n-10) -261189926549682*a(n-11) +1315848767909456*a(n-12) +10954607284537534*a(n-13) -164731785495495987*a(n-14) -1080885231798070753*a(n-15) +6337772915200237725*a(n-16) +61973915198240765682*a(n-17) -174926704521799076140*a(n-18) -1769876739708372407462*a(n-19) +4724328200626189593230*a(n-20) +28925367737640459827048*a(n-21) -118508927361522008394407*a(n-22) -338291074875836070162743*a(n-23) +2078500757367505073417544*a(n-24) +3638638083258148122104563*a(n-25) -22533121425170101610868173*a(n-26) -35951981794618984423807318*a(n-27) +148059589343607187758481730*a(n-28) +304066001010912610265678504*a(n-29) -543286472115259646014984432*a(n-30) -1895168824990397488205106938*a(n-31) +515323596470817357216859317*a(n-32) +8036722529928241722905535107*a(n-33) +4658674126315217994389185485*a(n-34) -23520333887240276023055681024*a(n-35) -26120175729257847332834731016*a(n-36) +47521762151458452659065279664*a(n-37) +72064304438839106911387954831*a(n-38) -41729033682747124756817612725*a(n-39) -100063538582590874708501775431*a(n-40) -48216552248752824661323541828*a(n-41) -38770983476975500704603496326*a(n-42) +69199895034873870415739037968*a(n-43) +280771337691101112841981861706*a(n-44) +184733821531685058029799283792*a(n-45) -163201452658375838142652433035*a(n-46) -228964026785686523613364343973*a(n-47) -122774246713934304910904367423*a(n-48) -155053344320588456470407890304*a(n-49) -99882809264047288476808827105*a(n-50) +53324812803037826578664372675*a(n-51) +201914092248708392950874791566*a(n-52) +271765815346088672075249306279*a(n-53) +248628574921061669273781811996*a(n-54) +15423737680329534006814267885*a(n-55) -209896022729096662804319861750*a(n-56) -229186442003419348720426706257*a(n-57) -120121785521481771433649205077*a(n-58) -7735080728966165564636600190*a(n-59) +56375234411286047939465681488*a(n-60) +75221248919842898190277039920*a(n-61) +45192898133556559556449870260*a(n-62) +11821114684373823010990217928*a(n-63) -8505240726855879856600819878*a(n-64) -11910243027909373556607800604*a(n-65) -8302725927108486632616630296*a(n-66) -2836261104383247082262276560*a(n-67) +156712866661252193796331328*a(n-68) +927231923402821571908741120*a(n-69) +683876449064791153012081664*a(n-70) +262930466460133858491167744*a(n-71) +33590254005629207243431936*a(n-72) -30497588710990717377200128*a(n-73) -24091194787071846063800320*a(n-74) -9341232987121533770268672*a(n-75) -1964473495355240679997440*a(n-76) +68495837187683634905088*a(n-77) +232862864734779755986944*a(n-78) +109343325199815281737728*a(n-79) +32753423481532588228608*a(n-80) +7654527620812080414720*a(n-81) +1428195666470526517248*a(n-82) +202075648864951468032*a(n-83) +20776019874734407680*a(n-84) for n>85
%e A198524 Some solutions for n=5
%e A198524 ..0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0
%e A198524 ..0..1..1..0....0..1..1..0....0..1..1..0....0..1..1..0....0..1..1..0
%e A198524 ..0..0..0..0....0..0..0..0....1..0..0..0....2..0..0..0....1..0..0..0
%e A198524 ..2..3..2..4....2..1..3..1....2..0..3..4....3..0..1..1....1..0..1..2
%e A198524 ..1..0..4..1....0..0..4..3....3..0..4..2....2..3..1..4....2..1..3..3
%K A198524 nonn
%O A198524 1,1
%A A198524 _R. H. Hardin_ Oct 26 2011