login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A223869
Number of 6Xn 0..3 arrays with rows and antidiagonals unimodal and columns nondecreasing
1
84, 7056, 303560, 8008548, 145947740, 1989679315, 21476594002, 191485393983, 1457018264594, 9708014658466, 57822416245144, 313064200874351, 1561981122439360, 7262269235529104, 31752205659432881, 131516275822916936
OFFSET
1,1
COMMENTS
Row 6 of A223864
LINKS
FORMULA
Empirical: a(n) = (1/48569119454267387884339200000000)*n^36 + (1/385469202017995141939200000000)*n^35 + (509/2294879094136521281765376000000)*n^34 + (45072673/3373472268380686284195102720000000)*n^33 + (98970929/155735580571551568517529600000000)*n^32 + (15657172481/622942322286206274070118400000000)*n^31 + (72553007/84245463642710408822784000000)*n^30 + (9224227575469/353670479749588078181744640000000)*n^29 + (259388109101239/365866013534056632601804800000000)*n^28 + (1069067947427789/60977668922342772100300800000000)*n^27 + (324068662301467/813035585631236961337344000000)*n^26 + (1050857599757983/125082397789421070974976000000)*n^25 + (3359228653373591/20330730290850174074880000000)*n^24 + (59499006518000473/19544124654597042339840000000)*n^23 + (328837729476779/6275036678399050383360000)*n^22 + (15779074497679499/19015262661815304192000000)*n^21 + (2751358950432231398341/235662488588764336619520000000)*n^20 + (50435698940805547445789/353493732883146504929280000000)*n^19 + (441377463056670747803689/296934735621843064140595200000)*n^18 + (1873830568342196532829127/141397493153258601971712000000)*n^17 + (267354503696336902783274977/2651202996623598786969600000000)*n^16 + (436422377507839553846644063/662800749155899696742400000000)*n^15 + (1125875946010062345791103079/304888344611713860501504000000)*n^14 + (2092746936332381279309322059/117264747927582254039040000000)*n^13 + (751942966419486002702371387/10125656687825770291200000000)*n^12 + (1974716117993688153795059/7436126973898022400000000)*n^11 + (1788367830018388939084527979/2198714023642167263232000000)*n^10 + (31107899679091365256605057767/14658093490947781754880000000)*n^9 + (211320747100198509737825012033/45147885997445373542400000000)*n^8 + (552453635986071137589553754293/63959505163047612518400000000)*n^7 + (32067365980652302617534655703/2434949582523040687104000000)*n^6 + (2243604186621342688240182563/137690601392671943616000000)*n^5 + (21949153806567016754942281/1376906013926719436160000)*n^4 + (391289317973804357849579/32783476522064748480000)*n^3 + (3883508589248023/569647119000960)*n^2 + (22960563482143/10314539492400)*n + 1
EXAMPLE
Some solutions for n=3
..0..0..0....0..0..0....0..0..0....0..0..0....0..2..1....0..2..3....0..0..0
..2..0..0....0..2..1....1..2..0....1..2..0....0..2..1....0..2..3....0..0..0
..2..3..1....2..3..2....1..2..1....2..2..1....0..2..2....0..3..3....1..0..0
..2..3..1....3..3..2....1..3..1....2..2..1....0..2..2....1..3..3....1..2..0
..2..3..1....3..3..2....1..3..2....2..2..1....3..2..2....2..3..3....1..2..0
..3..3..2....3..3..3....2..3..2....3..2..1....3..3..3....2..3..3....3..2..0
CROSSREFS
Sequence in context: A273438 A097840 A224177 * A224389 A223991 A224022
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 28 2013
STATUS
approved