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A078159 a(n) = A055086(2^n). 3
2, 3, 4, 7, 10, 15, 21, 31, 44, 63, 89, 127, 180, 255, 361, 511, 723, 1023, 1447, 2047, 2895, 4095, 5791, 8191, 11584, 16383, 23169, 32767, 46339, 65535, 92680, 131071, 185362, 262143, 370726, 524287, 741454, 1048575, 1482909, 2097151, 2965819, 4194303, 5931640, 8388607 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
a(2n-2)=2^n-1 and a(n)=2a(n-2)+1 generally.
LINKS
MATHEMATICA
Table[ Length[ Union[ Table[ Floor[2^w/j], {j, 1, 2^w}]]], {w, 1, 25}]
PROG
(PARI) a(n) = ceil(2*sqrt(2^n+1)) - 2; \\ Michel Marcus, Sep 02 2019
CROSSREFS
Sequence in context: A145467 A325341 A039841 * A129490 A018132 A329758
KEYWORD
nonn
AUTHOR
Labos Elemer, Nov 27 2002
EXTENSIONS
Extended by Robert G. Wilson v, Dec 02 2002
More terms from Michel Marcus, Sep 02 2019
STATUS
approved

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Last modified May 20 14:08 EDT 2024. Contains 372717 sequences. (Running on oeis4.)