A223803 Number of 4Xn 0..3 arrays with rows and antidiagonals unimodal

256, 65536, 4816168, 151310069, 2844578252, 37217420249, 370255807510, 2967702264487, 19953618004020, 115901407902175, 594677748128499, 2742258352954012, 11522283571283326, 44607717280309708, 160585424830894289

Offset

1,1

Comments

Row 4 of A223801

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = (1224989653/34469355651846635520000)*n^24 + (1274345773/470036667979726848000)*n^23 + (89684176061/749333818518405120000)*n^22 + (92332596599/25545471085854720000)*n^21 + (3678754549/45368802017280000)*n^20 + (80494587659/57244753133568000)*n^19 + (1442890795373/74694359900160000)*n^18 + (17944065812311/84031154887680000)*n^17 + (808497136964749/421803444142080000)*n^16 + (887979405310979/63270516621312000)*n^15 + (712542665498819/8497871585280000)*n^14 + (511835344841201/1255367393280000)*n^13 + (2484047083210032763/1546612628520960000)*n^12 + (29342532497594837/5751865147392000)*n^11 + (124717183755287231/9586441912320000)*n^10 + (524203224847641397/19772036444160000)*n^9 + (23382114961946647/547211427840000)*n^8 + (33110696329013011/640237370572800)*n^7 + (78034921690145238953/2128789257154560000)*n^6 - (394245218967404573/9855505820160000)*n^5 - (11421559789359613027/81307923016320000)*n^4 - (57003741297203/301945644000)*n^3 + (2875733400346871/11416863427200)*n^2 + (225454400125/1070845776)*n - 15

Example

Some solutions for n=3
..0..0..0....0..0..2....0..0..0....0..0..2....0..0..2....0..0..0....0..0..2
..0..0..3....0..2..3....2..2..1....0..2..3....1..2..0....1..2..0....1..2..0
..0..1..0....0..3..0....1..2..0....1..3..1....3..2..0....0..3..0....2..3..2
..1..2..2....3..0..0....0..3..3....0..0..3....0..3..3....1..1..3....3..3..3

Crossrefs

Sequence in context: A223878 A188909 A189110 * A223581 A133752 A144322

Adjacent sequences: A223800 A223801 A223802 * A223804 A223805 A223806

Keyword

nonn

Author

R. H. Hardin Mar 27 2013

Status

approved