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

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A188707 Number of 3 X n binary arrays without the pattern 0 0 diagonally or vertically. 1
 5, 21, 90, 387, 1665, 7164, 30825, 132633, 570690, 2455551, 10565685, 45461772, 195611805, 841673709, 3621533130, 15582644523, 67048623225, 288495182556, 1241330043105, 5341164667857, 22981833209970, 98885672046279 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Row 3 of A188706. LINKS R. H. Hardin, Table of n, a(n) for n = 1..200 C. Bautista-Ramos and C. Guillen-Galvan, Fibonacci numbers of generalized Zykov sums, J. Integer Seq., 15 (2012), #12.7.8. Index entries for linear recurrences with constant coefficients, signature (5,-3). FORMULA a(n) = 5*a(n-1) - 3*a(n-2). a(n) = [1,1;1,4]^(n-1).{1,2}.{1,2}. - John M. Campbell, Jul 09 2011 G.f.: x*(5 - 4*x)/(1 - 5*x + 3*x^2). - Colin Barker, Mar 11 2012 EXAMPLE Some solutions for 3 X 3: 1 1 0 1 0 0 1 1 0 1 0 0 0 0 0 1 0 0 0 0 1 1 1 1 1 1 1 1 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 1 1 1 0 0 1 1 0 0 1 0 0 1 1 1 1 0 1 1 MATHEMATICA LinearRecurrence[{5, -3}, {5, 21}, 22] (* Robert G. Wilson v, Jul 13 2011 *) PROG (PARI) \\ using formula by John M. Campbell a(n)=my(v=[1, 1; 1, 4]^(n-1)*[1, 2]~); v[1]*1+v[2]*2; \\ Joerg Arndt, Mar 19 2021 CROSSREFS Sequence in context: A273796 A035011 A113987 * A360580 A333538 A164037 Adjacent sequences: A188704 A188705 A188706 * A188708 A188709 A188710 KEYWORD nonn,easy AUTHOR R. H. Hardin, Apr 08 2011 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 June 8 00:26 EDT 2023. Contains 363157 sequences. (Running on oeis4.)