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A223977 Number of 4Xn 0..2 arrays with rows and antidiagonals unimodal 1
81, 6561, 186004, 2558848, 22935921, 153196498, 822895397, 3731866676, 14772553616, 52279545002, 168389072033, 500454038667, 1387317570171, 3618413260028, 8942729611918, 21066089007345, 47533740360251 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Row 4 of A223975
LINKS
FORMULA
Empirical: a(n) = (456419/5230697472000)*n^16 + (35741/12108096000)*n^15 + (4696759/65383718400)*n^14 + (1960073/1779148800)*n^13 + (31966559/2612736000)*n^12 + (461185847/4790016000)*n^11 + (496257731/914457600)*n^10 + (445395499/203212800)*n^9 + (228272848649/36578304000)*n^8 + (5589292243/435456000)*n^7 + (282633985/14370048)*n^6 + (3122820053/239500800)*n^5 - (91030209653/108972864000)*n^4 - (327561926401/4540536000)*n^3 + (185306939/3439800)*n^2 + (13865993/360360)*n + 7
EXAMPLE
Some solutions for n=3
..1..0..0....0..0..0....1..1..0....0..1..0....0..0..2....0..2..1....0..2..0
..2..2..1....1..2..2....1..2..0....2..1..0....1..1..2....0..2..0....0..1..1
..1..1..1....1..2..2....1..1..0....0..1..1....1..0..0....0..0..0....2..2..1
..0..1..0....2..1..0....0..2..0....0..1..0....0..2..1....0..2..0....0..0..2
CROSSREFS
Sequence in context: A206935 A206870 A181223 * A188565 A207087 A207181
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 30 2013
STATUS
approved

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Last modified July 15 07:46 EDT 2024. Contains 374324 sequences. (Running on oeis4.)