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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A252421 Number of (n+2)X(6+2) 0..3 arrays with every 3X3 subblock row and column sum not equal to 0 2 5 6 or 7 and every 3X3 diagonal and antidiagonal sum equal to 0 2 5 6 or 7 1
3719, 7186, 30724, 62288, 365974, 1757580, 3582225, 21882869, 107926383, 220463165, 1375056342, 6880842955, 14073466867, 88795680194, 447871169161, 916696939171, 5820110209906, 29480626550553, 60364093961967 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 6 of A252423

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = 135*a(n-3) -6200*a(n-6) +129658*a(n-9) -1479172*a(n-12) +10122008*a(n-15) -43818900*a(n-18) +123860492*a(n-21) -233367460*a(n-24) +297742037*a(n-27) -261058827*a(n-30) +159867108*a(n-33) -69122310*a(n-36) +20695032*a(n-39) -3955984*a(n-42) +409280*a(n-45) -16896*a(n-48) for n>56

EXAMPLE

Some solutions for n=4

..0..3..1..0..0..1..0..0....1..1..2..1..1..2..1..1....1..1..2..1..1..2..1..1

..0..0..1..3..0..1..0..0....3..0..1..0..0..1..3..0....3..0..1..0..0..1..0..3

..1..1..2..1..1..2..1..1....0..0..1..0..3..1..0..0....0..0..1..0..0..1..0..0

..0..0..1..0..0..1..0..0....1..1..2..1..1..2..1..1....1..1..2..1..1..2..1..1

..3..0..1..0..0..1..3..0....3..0..1..0..0..1..0..3....0..0..1..0..0..1..0..0

..1..1..2..1..1..2..1..1....0..0..1..0..0..1..0..0....3..0..1..3..0..1..0..0

CROSSREFS

Sequence in context: A252161 A180396 A158917 * A296908 A237736 A289512

Adjacent sequences:  A252418 A252419 A252420 * A252422 A252423 A252424

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 17 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 | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified July 11 17:04 EDT 2020. Contains 335626 sequences. (Running on oeis4.)