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!)
 A221266 Number of n X 2 arrays of occupancy after each element stays put or moves to some king-move neighbor, with no occupancy greater than 2. 1
 3, 19, 141, 1073, 8203, 62771, 480437, 3677345, 28147315, 215447091, 1649090685, 12622590641, 96616760123, 739531104531, 5660573328101, 43327576375905, 331641119361379, 2538471829096403, 19430157634105069, 148723740543110065 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Column 2 of A221269. LINKS R. H. Hardin, Table of n, a(n) for n = 1..66 FORMULA Empirical: a(n) = 10*a(n-1) - 19*a(n-2) + 8*a(n-3). Empirical g.f.: x*(1 - x)*(3 - 8*x) / (1 - 10*x + 19*x^2 - 8*x^3). - Colin Barker, Aug 04 2018 EXAMPLE Some solutions for n=3:   0 2   2 1   1 2   2 0   0 2   1 2   0 2   1 2   2 0   1 1   2 0   0 0   0 1   2 1   0 2   1 0   1 1   1 0   2 2   1 0   1 1   1 2   0 2   1 0   2 0   2 0   0 2   1 1   0 0   2 1 CROSSREFS Cf. A221269. Sequence in context: A074559 A027314 A025571 * A082758 A110525 A058859 Adjacent sequences:  A221263 A221264 A221265 * A221267 A221268 A221269 KEYWORD nonn AUTHOR R. H. Hardin, Jan 08 2013 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 6 21:48 EST 2019. Contains 329809 sequences. (Running on oeis4.)