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!)
 A297333 Number of n X 3 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 0 or 2 neighboring 1s. 1
 5, 22, 96, 421, 1847, 8105, 35568, 156089, 684994, 3006088, 13192185, 57893767, 254066201, 1114966916, 4893020877, 21472971950, 94233917248, 413544579709, 1814836148199, 7964389829833, 34951643113640, 153384927463937 (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) = 5*a(n-1) - 2*a(n-2) - 3*a(n-3). Empirical g.f.: x*(5 - 3*x - 4*x^2) / (1 - 5*x + 2*x^2 + 3*x^3). - Colin Barker, Feb 26 2019 EXAMPLE Some solutions for n=5: ..0..0..1. .0..0..0. .0..0..1. .1..0..1. .0..0..0. .0..1..0. .0..0..0 ..1..0..1. .0..0..1. .0..0..0. .1..0..1. .1..0..1. .0..1..1. .0..0..0 ..0..0..1. .1..0..1. .1..0..0. .0..0..0. .0..0..1. .1..1..0. .0..1..0 ..1..0..1. .0..0..0. .1..0..0. .0..1..1. .1..0..1. .0..1..0. .0..0..1 ..0..0..0. .0..0..1. .1..0..1. .1..1..0. .0..0..1. .0..0..1. .1..0..1 CROSSREFS Column 3 of A297338. Sequence in context: A266430 A083586 A200676 * A129158 A129164 A123347 Adjacent sequences:  A297330 A297331 A297332 * A297334 A297335 A297336 KEYWORD nonn AUTHOR R. H. Hardin, Dec 28 2017 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 1 22:24 EST 2020. Contains 338858 sequences. (Running on oeis4.)