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A216939 Number of side-3 hexagonal 0..n arrays with values nondecreasing E, SW and SE 1
52, 1211, 17336, 175869, 1374208, 8737047, 46978360, 219784500, 914221308, 3438633452, 11853180096, 37855195604, 113017101804, 317780021548, 846830343064, 2150149059905, 5225497612280, 12203607643755, 27481596234600 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Row 3 of A216937
LINKS
FORMULA
Empirical: a(n) = (1/5884534656000)*n^19 + (19/1176906931200)*n^18 + (2063/2853107712000)*n^17 + (127381/6276836966400)*n^16 + (3139187/7846046208000)*n^15 + (23993/4075868160)*n^14 + (3154906109/47076277248000)*n^13 + (437462609/724250419200)*n^12 + (2639011847/603542016000)*n^11 + (281346697/10973491200)*n^10 + (295058425993/2414168064000)*n^9 + (32651688991/68976230400)*n^8 + (158599063783/106991539200)*n^7 + (1749363777247/470762772480)*n^6 + (177682359077/24216192000)*n^5 + (26456060689/2377589760)*n^4 + (113155260151/9081072000)*n^3 + (178973011/18532800)*n^2 + (275861/60060)*n + 1
EXAMPLE
Some solutions for n=3
......0.0.0..........0.1.2..........0.1.1..........0.0.0..........0.0.0
.....0.1.2.3........1.2.2.2........0.1.1.3........0.0.0.0........0.0.0.3
....0.1.2.3.3......2.2.2.2.2......1.1.2.3.3......0.0.1.1.3......1.1.2.3.3
.....2.2.3.3........2.2.2.3........1.3.3.3........1.1.1.3........1.2.3.3
......2.3.3..........2.3.3..........3.3.3..........3.3.3..........2.3.3
CROSSREFS
Sequence in context: A160288 A133238 A331127 * A130000 A160153 A017768
KEYWORD
nonn
AUTHOR
R. H. Hardin Sep 20 2012
STATUS
approved

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Last modified June 17 03:50 EDT 2024. Contains 373432 sequences. (Running on oeis4.)