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A043567
Number of runs in base-15 representation of n.
4
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2
OFFSET
0,16
COMMENTS
Every positive integers occurs infinitely many times. See A297770 for a guide to related sequences.
LINKS
EXAMPLE
For n = 226, its base-15 representation is "101" as 226 = 1*(15^2) + 0*(15^1) + 1*(15^0). "101" has three runs, thus a(226) = 3.
For n = 482, its base-15 representation is "222" as 482 = 2*(15^2) + 2*(15^1) + 2*(15^0). "222" has just one run, thus a(482) = 1.
MATHEMATICA
Table[Length@ Split@ IntegerDigits[n, 15], {n, 0, 105}] (* Michael De Vlieger, Oct 10 2017 *)
PROG
(Scheme) (define (A043567 n) (let loop ((n n) (runs 1) (pd (modulo n 15))) (if (zero? n) runs (let ((d (modulo n 15))) (loop (/ (- n d) 15) (+ runs (if (not (= d pd)) 1 0)) d))))) ;; Antti Karttunen, Oct 10 2017
CROSSREFS
Cf. A043289, A043542, A297783 (number of distinct runs), A297770.
Sequence in context: A043541 A297783 A043542 * A297784 A043568 A043543
KEYWORD
nonn,base
EXTENSIONS
More terms from Antti Karttunen, Oct 10 2017
Updated by Clark Kimberling, Feb 04 2018
STATUS
approved