The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A251646 Number of (n+2)X(2+2) 0..3 arrays with no row, column, diagonal or antidiagonal in any 3X3 subblock summing to 0 2 4 5 7 or 9 1
448, 908, 1928, 4008, 10248, 22904, 49956, 129296, 300656, 689192, 1792064, 4317696, 10331264, 26936064, 66797136, 165179552, 431375936, 1092206912, 2762577872, 7222018464, 18536302352, 47560605216, 124411054752, 322001817152 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Column 2 of A251652
LINKS
FORMULA
Empirical: a(n) = 4*a(n-1) -2*a(n-2) +4*a(n-3) -36*a(n-4) +22*a(n-5) +59*a(n-6) -40*a(n-7) -20*a(n-8) +10*a(n-9) for n>15
EXAMPLE
Some solutions for n=4
..3..3..0..0....1..0..2..1....2..0..1..2....2..1..3..2....3..0..3..0
..1..1..1..1....0..2..1..3....0..1..2..0....1..0..2..1....0..0..3..3
..2..2..2..2....2..1..3..2....1..2..0..1....3..2..1..0....3..3..0..0
..3..0..3..0....1..0..2..1....2..3..1..2....2..1..0..2....0..0..3..3
..1..1..1..1....3..2..1..3....3..1..2..0....1..3..2..1....3..3..0..0
..2..2..2..2....2..1..0..2....1..2..0..1....3..2..1..0....0..0..3..3
CROSSREFS
Sequence in context: A153486 A062040 A093786 * A235177 A346514 A194648
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 06 2014
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.

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 19 00:22 EDT 2024. Contains 373492 sequences. (Running on oeis4.)