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A373470
First differences of A043555 = number of runs in base-3 representation of n.
1
0, 0, 1, -1, 1, 0, 0, -1, 1, 1, 0, -1, -1, 1, 1, 0, -1, 0, 1, 0, 0, -1, 1, -1, 0, -1, 1, 1, 0, 1, -1, 1, 0, 0, -1, -1, 1, 0, -1, -1, 1, 1, 0, -1, 1, 1, 0, 0, -1, 1, -1, 0, -1, 0, 1, 0, 1, -1, 1, 0, 0, -1, 0, 1, 0, -1, -1, 1, 1, 0, -1, -1, 1, 0, 0, -1, 1, -1, 0, -1, 1, 1, 0, 1, -1, 1, 0, 0, -1, 1, 1, 0, -1, -1, 1, 1, 0, -1, 0, 1
OFFSET
0
LINKS
Brad Klee, A new space-filling dragon curve theorem, on community.wolfram.com/groups, Jul 10, 2024
MAPLE
b:= n-> `if`(n<3, 1, b(iquo(n, 3))+`if`(n mod 9 in {0, 4, 8}, 0, 1)):
a:= n-> b(n+1)-b(n):
seq(a(n), n=0..99); # Alois P. Heinz, Jul 14 2024
PROG
(PARI) A373470(n)=A043555(n+1)-A043555(n) /* with {A043555(n)=my(d=digits(n, 3)); sum(i=2, #d, d[i]!=d[i-1])+1} */
CROSSREFS
Sequence in context: A287790 A285159 A073089 * A373141 A323158 A011657
KEYWORD
sign,base,less
AUTHOR
M. F. Hasler, Jul 13 2024
STATUS
approved