The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Please make a donation to keep the OEIS running. We are now in our 56th year. In the past year we added 10000 new sequences and reached almost 9000 citations (which often say "discovered thanks to the OEIS"). Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A255108 Number of length n+1 0..2 arrays with at most one downstep in every n consecutive neighbor pairs. 1
 9, 26, 66, 147, 294, 540, 927, 1507, 2343, 3510, 5096, 7203, 9948, 13464, 17901, 23427, 30229, 38514, 48510, 60467, 74658, 91380, 110955, 133731, 160083, 190414, 225156, 264771, 309752, 360624, 417945, 482307, 554337, 634698, 724090, 823251, 932958 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Row 1 of A255107. LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = (1/120)*n^5 + (1/6)*n^4 + (19/24)*n^3 + (11/6)*n^2 + (16/5)*n + 3. Empirical g.f.: x*(9 - 28*x + 45*x^2 - 39*x^3 + 17*x^4 - 3*x^5) / (1 - x)^6. - Colin Barker, Jan 24 2018 EXAMPLE Some solutions for n=4: ..1....1....0....0....0....1....0....0....1....2....0....0....1....1....0....0 ..1....2....0....0....0....1....1....1....1....1....2....2....2....0....0....0 ..0....0....2....2....1....2....0....1....1....2....2....2....2....0....2....2 ..0....2....1....0....1....2....0....2....1....2....2....1....0....0....2....0 ..1....2....1....2....2....1....1....1....2....2....0....2....2....0....1....1 CROSSREFS Cf. A255107. Sequence in context: A249275 A270695 A048468 * A048771 A055849 A235163 Adjacent sequences:  A255105 A255106 A255107 * A255109 A255110 A255111 KEYWORD nonn AUTHOR R. H. Hardin, Feb 14 2015 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 2 10:39 EST 2020. Contains 338876 sequences. (Running on oeis4.)