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A284580
Carryless base-2 product (A048720) of lengths of runs of 1-bits in binary representation of n.
3
1, 1, 1, 2, 1, 1, 2, 3, 1, 1, 1, 2, 2, 2, 3, 4, 1, 1, 1, 2, 1, 1, 2, 3, 2, 2, 2, 4, 3, 3, 4, 5, 1, 1, 1, 2, 1, 1, 2, 3, 1, 1, 1, 2, 2, 2, 3, 4, 2, 2, 2, 4, 2, 2, 4, 6, 3, 3, 3, 6, 4, 4, 5, 6, 1, 1, 1, 2, 1, 1, 2, 3, 1, 1, 1, 2, 2, 2, 3, 4, 1, 1, 1, 2, 1, 1, 2, 3, 2, 2, 2, 4, 3, 3, 4, 5, 2, 2, 2, 4, 2, 2, 4, 6, 2, 2, 2, 4, 4, 4, 6, 8, 3, 3, 3, 6, 3, 3, 6, 5, 4
OFFSET
0,4
EXAMPLE
a(119) = 5, as 119 is "1110111" in binary, and A048720(3,3) = 5.
PROG
(Scheme) (define (A284580 n) (reduce A048720bi 1 (bisect (reverse (binexp->runcount1list n)) (- 1 (modulo n 2))))) ;; Where A048720bi is a two-argument function implementing carryless binary product, A048720. For bisect and binexp->runcount1list, see under A227349.
CROSSREFS
Cf. A003714 (positions of ones).
Differs from similar A227349 for the first time at n=119, where a(119) = 5, while A227349(119) = 9.
Sequence in context: A038374 A284569 A272604 * A227349 A246028 A232186
KEYWORD
nonn,base
AUTHOR
Antti Karttunen, Apr 14 2017
STATUS
approved