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A183037 a(n) = A001511(n)*2^A001511(n) where A001511(n) equals the 2-adic valuation of 2n. 3
2, 8, 2, 24, 2, 8, 2, 64, 2, 8, 2, 24, 2, 8, 2, 160, 2, 8, 2, 24, 2, 8, 2, 64, 2, 8, 2, 24, 2, 8, 2, 384, 2, 8, 2, 24, 2, 8, 2, 64, 2, 8, 2, 24, 2, 8, 2, 160, 2, 8, 2, 24, 2, 8, 2, 64, 2, 8, 2, 24, 2, 8, 2, 896, 2, 8, 2, 24, 2, 8, 2, 64, 2, 8, 2, 24, 2, 8, 2, 160, 2, 8, 2, 24, 2, 8, 2, 64, 2, 8, 2, 24, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

2n/2^A001511(n) is odd for n >= 1, so that A001511(n) is logarithmic in nature.

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..16383

FORMULA

Logarithmic derivative of A183036.

EXAMPLE

L.g.f.: A(x) = 2*x + 8*x^2/2 + 2*x^3/3 + 24*x^4/4 + 2*x^5/5 + 8*x^6/6 + 2*x^7/7 + 64*x^8/8 + 2*x^9/9 + 8*x^10/10 + ...

The g.f. of A183036 begins:

exp(A(x)) = 1 + 2*x + 6*x^2 + 10*x^3 + 24*x^4 + 38*x^5 + 74*x^6 + ...

MATHEMATICA

Array[# 2^# &[IntegerExponent[#, 2] + 1] &, 93] (* Michael De Vlieger, Nov 06 2018 *)

PROG

(PARI) {a(n)=valuation(2*n, 2)*2^valuation(2*n, 2)}

CROSSREFS

Cf. A183036.

Sequence in context: A286455 A175183 A189217 * A063077 A245995 A085192

Adjacent sequences:  A183034 A183035 A183036 * A183038 A183039 A183040

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Dec 19 2010

STATUS

approved

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Last modified January 20 19:53 EST 2020. Contains 331096 sequences. (Running on oeis4.)