A037907 Number of i such that |d(i) - d(i-1)| = 1, where Sum_{i=0..m} d(i)*4^i is the base-4 representation of n.

0, 0, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 1, 2, 1, 1, 1, 0, 1, 0, 1, 2, 1, 2, 0, 0, 1, 0, 0, 1, 0, 0, 2, 1, 2, 1, 0, 1, 0, 1, 1, 1, 2, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 2, 1, 2, 0, 0, 1, 0, 1, 2, 1, 1, 3, 2, 3, 2, 1, 2, 1, 2, 1, 1, 2, 1, 1, 2, 1, 1, 1, 0, 1, 0, 1, 2, 1

Offset

1,17

Links

Iain Fox, Table of n, a(n) for n = 1..10000

Prog

(PARI) a(n) = my(c); for(i=2, #n=digits(n, 4), if(abs(n[i]-n[i-1])==1, c++)); c \\ Iain Fox, Oct 27 2018

Crossrefs

In base b: A037906 (b=3), A037908 (b=5), A037909 (b=6), A037910 (b=7), A037911 (b=8), A037912 (b=9), A037913 (b=10).

Sequence in context: A353454 A276799 A353423 * A365167 A037801 A340219

Adjacent sequences: A037904 A037905 A037906 * A037908 A037909 A037910

Keyword

nonn,base

Author

Clark Kimberling

Status

approved