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A246765
Decimal expansion of a limit associated with the asymptotic number of ways of writing a number as a sum of powers of 2, with each power used at most twice (cardinality of "alternating bit sets" of a given number, also known as Stern's diatomic sequence).
1
9, 5, 8, 8, 5, 4, 1, 9, 0, 8, 2, 4, 7, 6, 7, 3, 8, 3, 2, 0, 9, 0, 9, 4, 3, 0, 4, 2, 0, 3, 6, 5, 9, 2, 9, 5, 7, 4, 8, 6, 8, 2, 9, 9, 1, 0, 0, 5, 8, 5, 6, 9, 1, 4, 9, 1, 0, 0, 1, 9, 6, 7, 9, 2, 5, 9, 6, 5, 1, 8, 4, 0, 2, 1, 2, 3, 0, 7, 9, 6, 0, 1, 6, 9, 0, 3, 4, 9, 0, 7, 2, 2, 5, 7, 2, 5, 2, 8, 5, 8, 6, 4, 2
OFFSET
0,1
COMMENTS
See A002487.
REFERENCES
Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Section 2.16.3 Alternating bit sets, p. 148.
LINKS
Neil J. Calkin and Herbert S. Wilf, Binary Partitions of Integers and Stern-Brocot-Like Trees, 1998. Section 10, open question 9 (which is answered by Coons and Tyler).
Michael Coons and Jason Tyler, The maximal order of Stern's diatomic sequence. arXiv:1307.1521 [math.NT], 2013-2014.
Steven R. Finch, Errata and Addenda to Mathematical Constants, arXiv:2001.00578 [math.HO], 2020. See p. 20.
FORMULA
3^(log(phi)/log(2))/sqrt(5), where phi is the golden ratio.
EXAMPLE
0.95885419082476738320909430420365929574868299100585691491...
MATHEMATICA
RealDigits[ 3^(Log[GoldenRatio]/Log[2]) / Sqrt[5], 10, 103] // First
CROSSREFS
Cf. A002487.
Sequence in context: A146483 A090463 A272795 * A191759 A289505 A371528
KEYWORD
nonn,cons,easy
AUTHOR
STATUS
approved