A125537 Number of n X n arrays with entries in 1..7 in which adjacent entries differ by 4 or less (adjacent means in x or y directions).

1, 7, 1527, 11721313, 3050388738539, 27037458180935427547, 8157016618633297682357104957, 83768469285967811192253950787571671419, 29282610870399702055320868574328652947738735891523

Offset: 0

Author

R. H. Hardin, Dec 31 2006

Keywords

• nonn

Comments

[Empirical] a(base+1,n,diff)=a(base,n,diff)+F(n,diff) for base>=2.diff.(n-1) and F(n,diff)= (n=2, A063496(diff+1)) (n=3, A068744(diff+1)) (n=4, A068745(diff+1)) (n=5, A068746(diff+1)) (n=6, A068747(diff+1))