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A126412
Number of base 25 n-digit numbers with adjacent digits differing by two or less.
3
1, 25, 119, 575, 2793, 13611, 66473, 325149, 1592355, 7805655, 38292485, 187972885, 923231055, 4536538325, 22300261185, 109658861091, 539395083843, 2653895007787, 13060517277349, 64287300999691, 316495856518423
OFFSET
0,2
COMMENTS
[Empirical] a(base,n)=a(base-1,n)+5^(n-1) for base>=2n-1; a(base,n)=a(base-1,n)+5^(n-1)-2 when base=2n-2
PROG
(S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-2](($[i]`-$[i+1]`>2)+($[i+1]`-$[i]`>2))
CROSSREFS
Cf. Base 25 differing by one or less A126379.
Sequence in context: A218493 A360511 A124953 * A078815 A270368 A206472
KEYWORD
nonn,base
AUTHOR
R. H. Hardin, Dec 28 2006
STATUS
approved