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 A249845 Number of length 1+4 0..n arrays with no five consecutive terms having the maximum of any two terms equal to the minimum of the remaining three terms. 1
 10, 110, 560, 1920, 5170, 11830, 24080, 44880, 78090, 128590, 202400, 306800, 450450, 643510, 897760, 1226720, 1645770, 2172270, 2825680, 3627680, 4602290, 5775990, 7177840, 8839600, 10795850, 13084110, 15744960, 18822160, 22362770 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Row 1 of A249844. LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = n^5 + (5/2)*n^4 + (10/3)*n^3 + (5/2)*n^2 + (2/3)*n. Conjectures from Colin Barker, Aug 18 2017: (Start) G.f.: 10*x*(1 + x)*(1 + 4*x + x^2) / (1 - x)^6. a(n) = 6*a(n-1) - 15*a(n-2) + 20*a(n-3) - 15*a(n-4) + 6*a(n-5) - a(n-6) for n>6. (End) EXAMPLE Some solutions for n=6 ..5....6....6....3....5....0....4....5....4....0....3....1....6....0....3....5 ..0....3....6....4....3....5....1....4....3....1....5....2....3....1....1....3 ..6....0....2....3....2....0....6....6....2....0....4....3....5....0....5....1 ..1....2....1....2....1....4....4....1....5....3....1....3....3....2....4....4 ..2....5....3....1....6....6....2....1....5....2....0....3....6....2....4....0 CROSSREFS Sequence in context: A043996 A044723 A158492 * A180290 A110251 A270243 Adjacent sequences:  A249842 A249843 A249844 * A249846 A249847 A249848 KEYWORD nonn AUTHOR R. H. Hardin, Nov 07 2014 STATUS approved

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Last modified October 20 22:44 EDT 2019. Contains 328291 sequences. (Running on oeis4.)