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A250137
Number of length n+2 0..5 arrays with the medians of every three consecutive terms nondecreasing
1
216, 986, 4368, 19446, 79200, 311498, 1219944, 4617079, 17036428, 62297886, 224152970, 793463094, 2782588100, 9662944274, 33203799944, 113195928313, 383180556700, 1287749650878, 4300782679270, 14285051453226, 47196108008844
OFFSET
1,1
COMMENTS
Column 5 of A250140
LINKS
FORMULA
Empirical: a(n) = 6*a(n-1) -15*a(n-2) +90*a(n-3) -345*a(n-4) +626*a(n-5) -2672*a(n-6) +7542*a(n-7) -9364*a(n-8) +39880*a(n-9) -80843*a(n-10) +55688*a(n-11) -359451*a(n-12) +414422*a(n-13) -27827*a(n-14) +2167310*a(n-15) -323498*a(n-16) -838688*a(n-17) -8847573*a(n-18) -7284516*a(n-19) +188080*a(n-20) +21990816*a(n-21) +37266852*a(n-22) +19854080*a(n-23) -25109056*a(n-24) -77719328*a(n-25) -71695312*a(n-26) -8159616*a(n-27) +70525056*a(n-28) +97325568*a(n-29) +48155904*a(n-30) -15482880*a(n-31) -46172160*a(n-32) -33177600*a(n-33) -8294400*a(n-34)
EXAMPLE
Some solutions for n=5
..1....5....3....5....0....5....0....3....0....1....0....0....4....0....2....0
..2....3....0....0....0....3....3....2....1....1....4....1....3....5....0....4
..1....1....0....2....1....3....3....2....2....4....1....1....3....4....2....0
..1....3....0....2....0....3....1....2....1....0....4....1....3....1....4....3
..2....3....3....2....5....3....3....3....5....1....4....4....4....5....1....3
..3....5....2....2....4....2....5....5....3....2....1....1....5....4....4....4
..3....4....3....0....3....5....4....1....4....3....4....5....2....3....5....5
CROSSREFS
Sequence in context: A377845 A135590 A187859 * A109399 A111029 A124581
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 13 2014
STATUS
approved