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 A125530 Number of n X n arrays with entries in 1..3 in which adjacent entries differ by 1 or less (adjacent means in x or y directions). 0
 1, 3, 35, 2021, 536453, 661407975, 3780952160847, 100240477650720585, 12324646884990466825513, 7027467861520236770627093435, 18582989792598188051914777397933755 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 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)) LINKS PROG (S/R) stvar \$[N][N]:(0.. M-1) init \$[][]:=0 asgn \$[][]->{*} kill +[i in 0.. N-2](+[j in 0.. N-1]((\$[i][j]`-\$[i+1][j]`>1)+(\$[i+1][j]`-\$[i][j]`>1)+(\$[j][i]`-\$[j][i+1]`>1)+(\$[j][i+1]`-\$[j][i]`>1))) CROSSREFS Sequence in context: A006098 A320845 A012499 * A334253 A068726 A263512 Adjacent sequences:  A125527 A125528 A125529 * A125531 A125532 A125533 KEYWORD nonn AUTHOR R. H. Hardin, Dec 31 2006 STATUS approved

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Last modified August 6 10:01 EDT 2020. Contains 336245 sequences. (Running on oeis4.)