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A360649
The exponents that occur in the greedy representation of 1/2 as a sum of powers of 2/3.
0
2, 8, 11, 14, 16, 26, 33, 38, 45, 48, 51, 53, 65, 69, 72, 80, 83, 89, 94, 101, 105, 109, 115, 118, 123, 131, 139, 142, 148, 152, 157, 160, 164, 170, 176, 179, 182, 185, 188, 193, 197, 208, 214, 220, 223, 225, 232, 234, 240, 243, 247, 250, 254, 258, 261, 271
OFFSET
1,1
COMMENTS
These numbers correspond to the 1's in the (3/2)-expansion of 1/2, as defined by Renyi.
LINKS
W. Parry, On the beta-Expansions of Real Numbers, Acta Math. Acad. Sci. Hungar. 11, 401-416, 1960.
A. Renyi, Representations for real numbers and their ergodic properties, Acta Math. Acad. Sci. Hung. 8 (1957) 477-493.
FORMULA
a(n) = A077468(n+1) - 1. - Andrey Zabolotskiy, Nov 03 2024
EXAMPLE
The first power of 2/3 that is smaller than 1/2 is (2/3)^2, so the first term of the sequence is 2. Subtracting (2/3)^2 from 1/2 leaves 1/18. The first power of 2/3 that is less than 1/18 is (2/3)^8, so the next term of the sequence is 8.
MAPLE
x:= 1/2:
for i from 1 to 100 do
A[i]:= ceil(log[2/3](x));
x:= x-(2/3)^A[i];
od:
seq(A[i], i=1..100); # Robert Israel, Feb 15 2023
MATHEMATICA
PositionIndex[RealDigits[1/2, 3/2, 100, -1][[1]]][[2]]
CROSSREFS
Sequence in context: A287569 A216538 A077820 * A297831 A045086 A366915
KEYWORD
nonn,changed
AUTHOR
James Propp, Feb 15 2023
STATUS
approved