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A011754 Number of ones in the binary expansion of 3^n. 8
1, 2, 2, 4, 3, 6, 6, 5, 6, 8, 9, 13, 10, 11, 14, 15, 11, 14, 14, 17, 17, 20, 19, 22, 16, 18, 24, 30, 25, 25, 25, 26, 26, 34, 29, 32, 27, 34, 36, 32, 28, 39, 38, 39, 34, 34, 45, 38, 41, 33, 41, 46, 42, 35, 39, 42, 39, 40, 42, 48, 56, 56, 49, 57, 56, 51, 45, 47, 55, 55, 64, 68, 58 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Conjecture: a(n)/n tends to log(3)/(2*log(2)) = 0.792481250... (A094148). - Ed Pegg Jr, Dec 05 2002

a(n) = A000120(A000244(n)). - Reinhard Zumkeller, Aug 14 2015

REFERENCES

S. Wolfram, "A new kind of science", p. 903.

LINKS

T. D. Noe, Table of n, a(n) for n = 0..1000

FORMULA

a(n) = A000120(3^n). - Benoit Cloitre, Dec 06 2002

MATHEMATICA

Table[DigitCount[3^n, 2][[1]], {n, 0, 100}] (* Stefan Steinerberger, Apr 03 2006 *)

DigitCount[3^Range[0, 100], 2, 1] (* Harvey P. Dale, Apr 06 2012 *)

PROG

(Haskell)

a011754 = a000120 . a000244  -- Reinhard Zumkeller, Aug 14 2015

(PARI) a(n)=hammingweight(3^n) \\ Charles R Greathouse IV, Feb 09 2017

(MAGMA) [&+Intseq(3^n, 2): n in [0..79]]; // Vincenzo Librandi, Nov 28 2018

CROSSREFS

Cf. A007088, A000120, A000244, A004656, A261009, A001370, A094148.

Sequence in context: A053197 A301768 A088145 * A090105 A082146 A037145

Adjacent sequences:  A011751 A011752 A011753 * A011755 A011756 A011757

KEYWORD

nonn,nice,easy

AUTHOR

Allan C. Wechsler, Dec 11 1999

EXTENSIONS

More terms from Stefan Steinerberger, Apr 03 2006

STATUS

approved

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Last modified April 3 01:23 EDT 2020. Contains 333195 sequences. (Running on oeis4.)