This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A223785 #6 Jul 23 2025 04:30:36 %S A223785 46,2116,62365,1560013,39387861,1026135371,27088106846,715394830136, %T A223785 18858304684055,496722962933967,13083748459268997,344674592599166771, %U A223785 9080493561769780564,239226142956291614446,6302367997324565980625 %N A223785 Number of nX4 0..2 arrays with rows, diagonals and antidiagonals unimodal. %C A223785 Column 4 of A223789 %H A223785 R. H. Hardin, <a href="/A223785/b223785.txt">Table of n, a(n) for n = 1..210</a> %F A223785 Empirical: a(n) = 36*a(n-1) -189*a(n-2) -3541*a(n-3) +59127*a(n-4) -226113*a(n-5) -2332737*a(n-6) +9857697*a(n-7) +99543550*a(n-8) +95675691*a(n-9) -5724165128*a(n-10) +5396730978*a(n-11) +117801963183*a(n-12) +48822212002*a(n-13) -4050581859555*a(n-14) -9385185579247*a(n-15) +93974968759615*a(n-16) +418814395559996*a(n-17) -398631629899971*a(n-18) -8857200756180654*a(n-19) -17297999616825626*a(n-20) +61168241169556772*a(n-21) +315463283515803651*a(n-22) +213887059257798310*a(n-23) -1903664148042753413*a(n-24) -3584708139929595584*a(n-25) +1714913055484581266*a(n-26) +11096777221831756444*a(n-27) -7609600734685922241*a(n-28) -49783583957613699145*a(n-29) +229513376763785174005*a(n-30) +180988649676924655797*a(n-31) -501542105212285553370*a(n-32) -325246768938962167438*a(n-33) +1501252528314140198120*a(n-34) +5802160737866727525882*a(n-35) -16205743701771553347998*a(n-36) -12947461293194280857390*a(n-37) -36099351841893292475137*a(n-38) +81150506478189926731033*a(n-39) +315683614302924768396043*a(n-40) -678254108759024930127839*a(n-41) -174717381067845210519994*a(n-42) +1334495710753290909569152*a(n-43) +221178153601308790024930*a(n-44) -483252100375673175449627*a(n-45) -2714447412869195417032469*a(n-46) +1574170270974397211830313*a(n-47) +753869711211526732155023*a(n-48) -5395070252732438366552504*a(n-49) +4757066470991903272143408*a(n-50) +8876390245281412619998437*a(n-51) -1877127082673826201189221*a(n-52) -12865570823541965542911108*a(n-53) +2207607579231775223357612*a(n-54) +13699987590118569137971332*a(n-55) -9938636241626662896298108*a(n-56) -16701218412807619111473012*a(n-57) +8284692714173402914397700*a(n-58) +16110317416374339328207960*a(n-59) -4384172067171970298981184*a(n-60) -6240892805930542467867088*a(n-61) +6453778250708127079582832*a(n-62) +1554531273179700190700896*a(n-63) -3413324636388770330606720*a(n-64) -34723774750877869086976*a(n-65) -189654079977746620978816*a(n-66) -1002029019037833715250176*a(n-67) -163481539387725950018304*a(n-68) +145241176478505601837056*a(n-69) +105485623837957432606720*a(n-70) +101928363962749438431232*a(n-71) +53672511863761575182336*a(n-72) +11193681570052043833344*a(n-73) +225784053502893359104*a(n-74) -316491621666724773888*a(n-75) -131089967696959242240*a(n-76) -46043707372770164736*a(n-77) -9232452487045185536*a(n-78) -858153604115070976*a(n-79) -26310763496865792*a(n-80) %e A223785 Some solutions for n=3 %e A223785 ..0..0..2..1....1..2..1..1....0..1..2..1....0..2..2..0....0..1..1..1 %e A223785 ..1..2..2..1....0..1..2..1....2..1..1..0....0..0..1..0....0..2..2..0 %e A223785 ..0..2..1..0....0..1..1..1....1..2..2..2....0..2..1..1....0..0..0..0 %K A223785 nonn %O A223785 1,1 %A A223785 _R. H. Hardin_ Mar 27 2013