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A020911
Number of digits in the base 3 representation of n-th Fibonacci number.
0
1, 1, 1, 2, 2, 2, 3, 3, 4, 4, 5, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 9, 10, 10, 11, 11, 12, 12, 12, 13, 13, 14, 14, 15, 15, 16, 16, 16, 17, 17, 18, 18, 19, 19, 19, 20, 20, 21, 21, 22, 22, 23, 23, 23, 24, 24, 25, 25, 26, 26, 26, 27, 27, 28, 28, 29, 29, 30, 30, 30
OFFSET
1,4
FORMULA
a(n) = A081604(A000045(n)). - Andrew Howroyd, Jan 01 2020
MATHEMATICA
IntegerLength[Fibonacci[Range[50]], 3] (* Harvey P. Dale, Aug 13 2018 *)
PROG
(PARI) a(n)={1 + logint(fibonacci(n), 3)} \\ Andrew Howroyd, Jan 01 2020
(Magma) [#Intseq(Fibonacci(n), 3):n in [1..70]]; // Marius A. Burtea, Jan 02 2020
CROSSREFS
Cf. A000045 (Fibonacci numbers), A081604 (base-3 digits of n).
Sequence in context: A114540 A183142 A121830 * A336861 A029125 A074990
KEYWORD
nonn,base
EXTENSIONS
Offset corrected and terms a(50) and beyond from Andrew Howroyd, Jan 01 2020
STATUS
approved