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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 REFERENCES S. Wolfram, "A new kind of science", p. 903. LINKS T. D. Noe, Table of n, a(n) for n = 0..1000 Taylor Dupuy, David E. Weirich, Bits of 3^n in binary, Wieferich primes and a conjecture of ErdÅ‘s, Journal of Number Theory, Volume 158, January 2016, Pages 268-280. FORMULA a(n) = A000120(3^n). - Benoit Cloitre, Dec 06 2002 a(n) = A000120(A000244(n)). - Reinhard Zumkeller, Aug 14 2015 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 August 13 02:09 EDT 2020. Contains 336441 sequences. (Running on oeis4.)