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A250085 Number of length 4+5 0..n arrays with every six consecutive terms having the maximum of some two terms equal to the minimum of the remaining four terms. 1
252, 5084, 42936, 222329, 847708, 2623376, 6978064, 16547001, 35852668, 72229740, 137044040, 247259649, 427412636, 712054192, 1148730272, 1801569169, 2755552764, 4121551516, 6042207576, 8698754729, 12318868188, 17185641584 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = (3/28)*n^8 + (121/35)*n^7 + (85/4)*n^6 + (501/10)*n^5 + (249/4)*n^4 + (1717/30)*n^3 + (1159/28)*n^2 + (1597/105)*n + 1.
Conjectures from Colin Barker, Nov 11 2018: (Start)
G.f.: x*(252 + 2816*x + 6252*x^2 - 2239*x^3 - 2861*x^4 + 56*x^5 + 52*x^6 - 9*x^7 + x^8) / (1 - x)^9.
a(n) = 9*a(n-1) - 36*a(n-2) + 84*a(n-3) - 126*a(n-4) + 126*a(n-5) - 84*a(n-6) + 36*a(n-7) - 9*a(n-8) + a(n-9) for n>9.
(End)
EXAMPLE
Some solutions for n=3:
3 2 2 0 2 2 3 3 3 2 1 0 1 0 3 1
0 0 2 2 0 3 3 3 3 2 0 3 1 2 3 1
2 1 1 2 0 0 3 2 1 0 0 3 3 2 2 1
3 0 1 0 2 1 0 0 1 3 2 2 1 0 1 1
2 0 0 0 0 1 0 0 3 2 2 0 1 0 1 3
2 1 2 0 0 2 0 0 1 2 0 0 2 0 1 3
2 0 1 1 0 2 2 0 1 2 1 0 1 3 3 0
3 2 1 3 0 2 1 0 1 2 0 3 2 3 2 1
0 1 3 1 1 0 0 3 1 2 0 3 3 0 0 3
CROSSREFS
Row 4 of A250081.
Sequence in context: A169713 A099059 A151610 * A024018 A270853 A177301
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 11 2014
STATUS
approved

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Last modified April 13 05:19 EDT 2024. Contains 371639 sequences. (Running on oeis4.)