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A124953
Number of base 25 circular n-digit numbers with adjacent digits differing by 2 or less.
1
1, 25, 119, 445, 1947, 8575, 38747, 177223, 819187, 3816247, 17891349, 84312583, 399037959, 1895486995, 9032061297, 43155077395, 206685100995, 991968231607, 4769763119885, 22973188788967, 110815066535017, 535263089155897
OFFSET
0,2
COMMENTS
[Empirical] a(base,n)=a(base-1,n)+A005191(n+1) for base>=2.int(n/2)+1.
See A285280 for confirmation of linear recurrence and code to produce sequence. - Ray Chandler, Aug 12 2023.
LINKS
Index entries for linear recurrences with constant coefficients, signature (25, -253, 1265, -2674, -2240, 21374, -23256, -51850, 111350, 49001, -222697, 3926, 248990, -47344, -166462, 41345, 66379, -16465, -14979, 3200, 1700, -265, -75, 5, 1).
PROG
(S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-1](($[i]`-$[(i+1)mod N]`>2)+($[(i+1)mod N]`-$[i]`>2))
CROSSREFS
Cf. Row 25 of A285280.
Sequence in context: A020152 A218493 A360511 * A126412 A078815 A270368
KEYWORD
nonn,base
AUTHOR
R. H. Hardin, Dec 28 2006
STATUS
approved