The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A250392 Number of length 6+3 0..n arrays with no four consecutive terms having the maximum of any two terms equal to the minimum of the remaining two terms. 2
 6, 966, 26578, 309452, 2160160, 10755158, 42158796, 138336744, 395723154, 1015071750, 2382851790, 5197343476, 10655843900, 20723014006, 38504379320, 68753342352, 118544772606, 198153311046, 322179959658, 510976323420 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Row 6 of A250387. LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = n^9 - (7/30)*n^8 + (1229/315)*n^7 - (23/30)*n^6 + (49/36)*n^5 + (67/30)*n^4 - (493/180)*n^3 + (53/30)*n^2 - (11/21)*n. Conjectures from Colin Barker, Aug 20 2017: (Start) G.f.: 2*x*(3 + 453*x + 8594*x^2 + 43211*x^3 + 73495*x^4 + 45443*x^5 + 9692*x^6 + 549*x^7) / (1 - x)^10. a(n) = 10*a(n-1) - 45*a(n-2) + 120*a(n-3) - 210*a(n-4) + 252*a(n-5) - 210*a(n-6) + 120*a(n-7) - 45*a(n-8) + 10*a(n-9) - a(n-10) for n>10. (End) EXAMPLE Some solutions for n=3: ..0....2....2....1....0....2....2....0....3....0....1....0....0....0....2....1 ..2....3....0....3....1....0....0....2....0....1....0....3....1....0....0....3 ..3....3....2....3....0....1....0....1....3....0....0....2....3....3....2....3 ..0....2....1....2....2....3....3....3....0....2....2....0....2....2....0....2 ..1....1....0....0....3....2....1....0....2....3....3....1....0....0....3....0 ..3....3....0....3....1....3....2....0....1....0....3....3....3....1....3....3 ..3....3....3....0....0....1....0....2....2....1....0....2....3....2....2....1 ..0....0....1....3....0....3....3....1....1....0....0....3....0....0....0....3 ..0....1....0....0....2....0....0....3....3....1....2....2....1....2....0....0 CROSSREFS Sequence in context: A175554 A263423 A266598 * A145250 A332196 A024085 Adjacent sequences: A250389 A250390 A250391 * A250393 A250394 A250395 KEYWORD nonn AUTHOR R. H. Hardin, Nov 20 2014 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified May 28 22:21 EDT 2023. Contains 363028 sequences. (Running on oeis4.)