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A270743
Runlength sequence of the zero-one sequence A270742.
2
1, 1, 2, 1, 2, 4, 1, 3, 6, 1, 4, 8, 1, 5, 10, 1, 6, 12, 1, 7, 14, 1, 8, 16, 1, 9, 18, 1, 10, 20, 1, 11, 22, 1, 12, 24, 1, 13, 26, 1, 14, 28, 1, 15, 30, 1, 16, 32, 1, 17, 34, 1, 18, 36, 1, 19, 38, 1, 20, 40, 1, 21, 42, 1, 22, 44, 1, 23, 46, 1, 24, 48, 1, 25
OFFSET
1,3
COMMENTS
This is the runlength sequence for C = (1/2)*(3/4)*(7/8)*(15/16)... in each base (2,3,4,...); for base 10, we have C = 0.8900100999989990000001000..., as in A132038.
LINKS
FORMULA
a(3n) = 2n for n > 0, a(3n+1) = 1 for n >= 0, a(3n+2) = n + 1 for n >= 0.
EXAMPLE
(zero-one sequence at A270742) = (0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0,...), with first 6 runs 0, 1, 00, 1, 00, 1111 of lengths 1,1,2,1,2,4.
MATHEMATICA
d = Join[{0}, RealDigits[QPochhammer[1/2], 2, 200000][[1]]];
u = Map[Length, Split[d]]
CROSSREFS
Sequence in context: A087704 A165092 A306915 * A209750 A156042 A287691
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Apr 04 2016
STATUS
approved