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 A065334 2-exponents to represent 3-smooth numbers (A065332). 3
 0, 1, 0, 2, 0, 1, 0, 3, 0, 0, 0, 2, 0, 0, 0, 4, 0, 1, 0, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 5, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5, 0, 0, 0, 0, 0, 0, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS For k > 0 with A065332(k) > 0: A065332(k) = (2^a(k)) * (3^A065335(k)). LINKS Antti Karttunen, Table of n, a(n) for n = 1..16384 Antti Karttunen, Data supplement: n, a(n) computed for n = 1..100000 FORMULA a(n) = A007814(n) * A065333(n). MATHEMATICA a[n_] := If[n/2^(e = IntegerExponent[n, 2])/3^IntegerExponent[n, 3] == 1, e, 0]; Array[a, 100] (* Amiram Eldar, Feb 21 2021 *) PROG (PARI) A065334(n) = if(1==n, 0, my(f = factor(n)); if(f[#f~, 1] > 3, 0, valuation(n, 2))); \\ Antti Karttunen, Oct 09 2018 CROSSREFS Cf. A007814, A065332, A065333, A065335. Sequence in context: A103775 A331594 A093057 * A356945 A162590 A276424 Adjacent sequences: A065331 A065332 A065333 * A065335 A065336 A065337 KEYWORD nonn,look AUTHOR Reinhard Zumkeller, Oct 29 2001 EXTENSIONS Typo in formula corrected, erroneous comment removed by Antti Karttunen, Oct 09 2018 STATUS approved

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Last modified December 7 07:00 EST 2022. Contains 358649 sequences. (Running on oeis4.)