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A224175
Number of 4 X n 0..3 arrays with rows and antidiagonals unimodal and columns nondecreasing.
1
35, 1225, 22988, 272130, 2335459, 15925611, 91494280, 459681672, 2071283343, 8522430293, 32452346859, 115542470121, 387735671674, 1234254138386, 3746228897820, 10888055937498, 30409729685443, 81862695894551
OFFSET
1,1
COMMENTS
Row 4 of A224173.
LINKS
FORMULA
Empirical: a(n) = (1/2906843957821440000)*n^24 + (1/80745665495040000)*n^23 + (40627/53523844179886080000)*n^22 + (149/6436248698880000)*n^21 + (6593077/9731608032706560000)*n^20 + (3395111/221172909834240000)*n^19 + (6648319/21341245685760000)*n^18 + (58653979/10670622842880000)*n^17 + (28432949/331085905920000)*n^16 + (2936797909/2510734786560000)*n^15 + (18556527629/1369491701760000)*n^14 + (39701629159/289700167680000)*n^13 + (122790999059713/110472330608640000)*n^12 + (19552381958779/2510734786560000)*n^11 + (343066282192637/7532204359680000)*n^10 + (2966503457023/14265538560000)*n^9 + (24242241250827793/32011868528640000)*n^8 + (16514299013828449/8002967132160000)*n^7 + (364205524025441321/152056375511040000)*n^6 + (32838681788587261/2111894104320000)*n^5 - (148032441802153/14768490240000)*n^4 - (1586985136748719/5866372512000)*n^3 + (228836377537124017/148419224553600)*n^2 - (1300791949339/411863760)*n + 2639 for n>2.
EXAMPLE
Some solutions for n=3
..0..0..1....0..3..1....1..2..0....0..1..1....0..1..1....0..1..1....0..1..0
..0..2..3....3..3..1....1..3..3....0..2..2....0..1..3....1..2..1....3..1..1
..1..2..3....3..3..1....3..3..3....0..2..2....0..3..3....1..2..2....3..2..1
..2..2..3....3..3..3....3..3..3....3..2..2....2..3..3....3..3..3....3..2..2
CROSSREFS
Cf. A224173.
Sequence in context: A207447 A207745 A207722 * A223867 A095153 A223989
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 31 2013
STATUS
approved