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

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A263375 Number of (n+1) X (1+1) 0..4 arrays with each row and column divisible by 9, read as a base-5 number with top and left being the most significant digits. 1
 2, 4, 11, 31, 89, 253, 748, 2214, 6615, 19767, 59217, 177393, 531930, 1595052, 4784427, 14351103, 43051113, 129146733, 387433620, 1162281150, 3486823767, 10460412279, 31381177761, 94143356001, 282429890802, 847289140884 (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) = 3*a(n-1) + 3*a(n-2) - 9*a(n-3) + 3*a(n-6) - 9*a(n-7) - 9*a(n-8) + 27*a(n-9). Empirical g.f.: x*(2 - 2*x - 7*x^2 + 4*x^3 - x^4 - 8*x^5 - 5*x^6 + 18*x^7 + 27*x^8) / ((1 - 3*x)*(1 - 3*x^2)*(1 - 3*x^6)). - Colin Barker, Jan 01 2019 EXAMPLE Some solutions for n=4: ..3..3....0..0....3..3....0..0....3..3....3..3....0..0....1..4....3..3....0..0 ..0..0....0..0....0..0....1..4....1..4....0..0....0..0....3..3....3..3....0..0 ..0..0....3..3....3..3....3..3....1..4....0..0....3..3....0..0....3..3....0..0 ..1..4....1..4....0..0....3..3....0..0....3..3....3..3....1..4....1..4....0..0 ..1..4....1..4....3..3....1..4....0..0....0..0....0..0....3..3....1..4....0..0 CROSSREFS Column 1 of A263382. Sequence in context: A325922 A148160 A148161 * A148162 A148163 A274775 Adjacent sequences:  A263372 A263373 A263374 * A263376 A263377 A263378 KEYWORD nonn AUTHOR R. H. Hardin, Oct 16 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 September 26 20:34 EDT 2021. Contains 347672 sequences. (Running on oeis4.)