This site is supported by donations to The OEIS Foundation.

 Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing. Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A250340 Number of length 4+5 0..n arrays with every six consecutive terms having the maximum of some three terms equal to the minimum of the remaining three terms. 1
 172, 4409, 37824, 193437, 725596, 2210213, 5794496, 13561449, 29037004, 57870241, 108719744, 194381733, 333198204, 550785901, 882129536, 1374085265, 2088343020, 3104898889, 4526091328, 6481257581, 9132069276, 12678608757, 17366250304 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = (9/140)*n^8 + (27/10)*n^7 + 19*n^6 + 48*n^5 + (1203/20)*n^4 + (1189/30)*n^3 + (81/14)*n^2 - (13/3)*n + 1. Conjectures from Colin Barker, Nov 12 2018: (Start) G.f.: x*(172 + 2861*x + 4335*x^2 - 2703*x^3 - 2357*x^4 + 227*x^5 + 65*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=4: ..1....1....0....2....2....1....0....1....1....1....1....1....0....0....1....0 ..4....1....0....2....1....4....2....2....2....2....0....2....2....1....3....4 ..2....0....2....0....1....0....2....1....1....3....2....2....4....2....1....4 ..3....1....4....4....3....4....2....2....0....3....4....2....2....2....2....4 ..2....1....3....3....2....2....4....2....1....3....3....0....0....2....1....4 ..0....2....2....0....2....2....3....3....4....4....2....4....4....3....1....4 ..2....2....2....2....4....2....1....4....1....1....2....2....2....2....1....2 ..4....0....1....2....0....4....1....0....3....0....1....2....2....4....1....4 ..0....1....1....1....0....0....2....2....0....3....1....3....3....1....0....4 CROSSREFS Row 4 of A250336. Sequence in context: A214115 A250968 A264213 * A035828 A259017 A097845 Adjacent sequences:  A250337 A250338 A250339 * A250341 A250342 A250343 KEYWORD nonn AUTHOR R. H. Hardin, Nov 19 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 | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified December 10 04:15 EST 2019. Contains 329885 sequences. (Running on oeis4.)