

A125541


Number of n X n arrays with entries in 1..9 in which adjacent entries differ by 6 or less (adjacent means in x or y directions).


0




OFFSET

0,2


COMMENTS

[Empirical] a(base+1,n,diff)=a(base,n,diff)+F(n,diff) for base>=2.diff.(n1) 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))


LINKS



PROG

(S/R) stvar $[N][N]:(0.. M1) init $[][]:=0 asgn $[][]>{*} kill +[i in 0.. N2](+[j in 0.. N1](($[i][j]`$[i+1][j]`>6)+($[i+1][j]`$[i][j]`>6)+($[j][i]`$[j][i+1]`>6)+($[j][i+1]`$[j][i]`>6)))


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



