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!)
A254991 Number of (n+2)X(1+2) 0..1 arrays with every 3X3 subblock sum of the two medians of the diagonal and antidiagonal minus the sum of the medians of the central row and column nondecreasing horizontally and vertically 2
512, 2679, 10762, 44548, 193488, 827673, 3456356, 14347670, 59706588, 248566303, 1033130316, 4290307069, 17817336950, 74000251757, 307313144732, 1276118644644, 5299027913826, 22004176592350, 91371821842232 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Column 1 of A254998
LINKS
FORMULA
Empirical: a(n) = 8*a(n-1) -23*a(n-2) +44*a(n-3) -66*a(n-4) -8*a(n-5) +140*a(n-6) -330*a(n-7) +1242*a(n-8) -2238*a(n-9) +3095*a(n-10) -3686*a(n-11) +800*a(n-12) +3024*a(n-13) -10566*a(n-14) +29630*a(n-15) -49344*a(n-16) +46186*a(n-17) -50188*a(n-18) +48446*a(n-19) +15531*a(n-20) -117740*a(n-21) +178416*a(n-22) -218922*a(n-23) +361814*a(n-24) -321718*a(n-25) +46758*a(n-26) +27060*a(n-27) -20770*a(n-28) +400582*a(n-29) -819637*a(n-30) +440604*a(n-31) +150305*a(n-32) +416494*a(n-33) -832954*a(n-34) -170232*a(n-35) +836549*a(n-36) +137570*a(n-37) -854341*a(n-38) -351998*a(n-39) +1162124*a(n-40) +31976*a(n-41) -958036*a(n-42) +16048*a(n-43) +573824*a(n-44) -177168*a(n-45) -427248*a(n-46) +99264*a(n-47) +163584*a(n-48) -13824*a(n-49) -20736*a(n-50) for n>54
EXAMPLE
Some solutions for n=4
..0..0..1....1..0..1....0..0..0....0..1..0....1..1..0....0..0..0....0..1..1
..0..0..1....1..0..1....0..0..0....0..0..0....0..1..1....1..1..1....0..1..1
..0..1..1....1..1..0....1..1..0....1..0..0....1..1..1....1..1..0....1..0..1
..1..1..1....0..0..1....1..0..0....0..1..0....0..1..1....0..0..1....1..0..0
..1..0..1....0..0..1....0..1..1....0..1..0....0..0..1....0..1..1....1..0..0
..1..0..1....1..1..0....1..1..0....0..1..1....0..0..1....1..1..1....0..1..1
CROSSREFS
Sequence in context: A254982 A258511 A254998 * A186840 A224643 A186832
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 11 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 | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 28 18:04 EDT 2024. Contains 371254 sequences. (Running on oeis4.)