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A197397
Number of nX4 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,3,1,1,1 for x=0,1,2,3,4
1
1, 17, 81, 547, 2571, 13397, 78101, 423957, 2255611, 12173719, 66864485, 361733507, 1953439221, 10607016995, 57610139877, 312099473393, 1691511381425, 9176876436943, 49767044309153, 269799849310117, 1462993236129599
OFFSET
1,2
COMMENTS
Every 0 is next to 0 3's, every 1 is next to 1 3's, every 2 is next to 2 1's, every 3 is next to 3 1's, every 4 is next to 4 1's
Column 4 of A197401
LINKS
FORMULA
Empirical: a(n) = a(n-1) +16*a(n-2) +64*a(n-3) +194*a(n-4) -769*a(n-5) -4478*a(n-6) -7191*a(n-7) +1136*a(n-8) +98749*a(n-9) +305317*a(n-10) +113031*a(n-11) -855145*a(n-12) -3960103*a(n-13) -8003637*a(n-14) +6071312*a(n-15) +36866250*a(n-16) +54532523*a(n-17) +52323382*a(n-18) -222157684*a(n-19) -611450451*a(n-20) +139402996*a(n-21) +736924244*a(n-22) +1439732752*a(n-23) +4649367188*a(n-24) -5903777248*a(n-25) -1570629136*a(n-26) +31735304480*a(n-27) -37013117504*a(n-28) -37562412736*a(n-29) -76709663168*a(n-30) -402344530816*a(n-31) +154749368320*a(n-32) +453668937216*a(n-33) +391049388032*a(n-34) +1241962704896*a(n-35) -851087351808*a(n-36) -372069908480*a(n-37) +117954953216*a(n-38) +338885148672*a(n-39) -970218274816*a(n-40) -282461732864*a(n-41) +279479058432*a(n-42) -13514047488*a(n-43) -5435817984*a(n-44)
EXAMPLE
Some solutions containing all values 0 to 4 for n=5
..1..3..1..0....1..3..1..0....1..3..1..2....2..1..3..1....2..1..3..1
..0..1..0..1....2..1..4..1....0..1..4..1....1..4..1..2....1..4..1..2
..0..0..1..3....0..0..1..3....1..4..1..3....3..1..0..0....3..1..2..0
..0..1..4..1....0..2..1..1....3..1..0..1....1..4..1..0....1..0..0..0
..1..3..1..2....0..1..3..1....1..0..0..0....0..1..3..1....0..0..0..0
CROSSREFS
Sequence in context: A373523 A373518 A347501 * A354012 A053826 A351267
KEYWORD
nonn
AUTHOR
R. H. Hardin Oct 14 2011
STATUS
approved