login
A125358
Number of base 21 circular n-digit numbers with adjacent digits differing by 4 or less.
0
1, 21, 169, 1101, 8369, 64671, 511957, 4108671, 33331889, 272616609, 2244091579, 18568201871, 154285123493, 1286408940149, 10756655080753, 90159207784161, 757192897525073, 6369787770505701, 53659598197631131, 452559057596166759
OFFSET
0,2
COMMENTS
[Empirical] a(base,n)=a(base-1,n)+A025014(n+1) for base>=4.int(n/2)+1
PROG
(S/R) stvar $[N]:(0..M-1) init $[]:=0 asgn $[]->{*} kill +[i in 0..N-1](($[i]`-$[(i+1)mod N]`>4)+($[(i+1)mod N]`-$[i]`>4))
CROSSREFS
Sequence in context: A278992 A358930 A041848 * A126516 A241219 A185128
KEYWORD
nonn,base
AUTHOR
R. H. Hardin, Dec 28 2006
STATUS
approved