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A037906
Number of i such that |d(i) - d(i-1)| = 1, where Sum_{i=0..m} d(i)*3^i is the base-3 representation of n.
8
0, 0, 1, 0, 1, 0, 1, 0, 1, 2, 1, 1, 0, 1, 1, 2, 1, 0, 1, 0, 2, 1, 2, 0, 1, 0, 1, 2, 1, 3, 2, 3, 1, 2, 1, 1, 2, 1, 1, 0, 1, 1, 2, 1, 1, 2, 1, 3, 2, 3, 1, 2, 1, 0, 1, 0, 2, 1, 2, 0, 1, 0, 2, 3, 2, 2, 1, 2, 2, 3, 2, 0, 1, 0, 2, 1, 2, 0, 1, 0, 1, 2, 1, 3, 2, 3, 1, 2, 1, 3
OFFSET
1,10
PROG
(PARI) a(n) = my(c); for(i=2, #n=digits(n, 3), if(abs(n[i]-n[i-1])==1, c++)); c \\ Iain Fox, Oct 27 2018
CROSSREFS
In base b: A037907 (b=4), A037908 (b=5), A037909 (b=6), A037910 (b=7), A037911 (b=8), A037912 (b=9), A037913 (b=10).
Sequence in context: A257988 A340379 A075685 * A319394 A278347 A120936
KEYWORD
nonn,base
STATUS
approved