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A143069
Least number k such that n*k has the fewest possible ones in its binary expansion.
3
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 5, 1, 1, 1, 1, 1, 27, 1, 1, 3, 3, 1, 41, 5, 19, 1, 565, 1, 1, 1, 1, 1, 1, 1, 7085, 27, 7, 1, 25, 1, 3, 3, 1, 3, 11, 1, 1, 41, 1, 5, 1266205, 19, 7, 1, 9, 565, 9099507, 1, 17602325, 1, 1, 1, 1, 1, 128207979, 1, 1, 1, 119, 1, 1, 7085, 1, 27, 5, 7, 13
OFFSET
1,11
COMMENTS
a(n)=1 indicates that n is a sturdy number (A125121); that is, no multiple of n has fewer ones than the binary expansion of n. A086342(n) gives the least possible number of ones in the binary expansion of a multiple of n. Compare with A143073.
LINKS
Trevor Clokie et al., Computational Aspects of Sturdy and Flimsy Numbers, arxiv preprint arXiv:2002.02731 [cs.DS], February 7 2020.
CROSSREFS
Sequence in context: A197152 A337668 A176907 * A010286 A340074 A344592
KEYWORD
nonn
AUTHOR
T. D. Noe, Jul 22 2008
STATUS
approved