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A089262
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2^[log2(n)] - 2^[log2(n*2/3)].
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0
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0, 0, 1, 0, 2, 2, 0, 0, 4, 4, 4, 4, 0, 0, 0, 0, 8, 8, 8, 8, 8, 8, 8, 8, 0, 0, 0, 0, 0, 0, 0, 0, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,5
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FORMULA
| a(2n) = 2a(n) + [n==1], a(2n+1) = 2a(n).
G.f. 1/(1-x) * sum(k>=0, 2^k*(t^2-t^3), t=x^2^k).
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PROG
| (PARI) a(n)=if(n<1, 0, if(n%2==0, 2*a(n/2)+(n/2==1), 2*a((n-1)/2)))
(PARI) a(n)=2^floor(log(n)/log(2))-2^floor(log(n*2/3)/log(2))
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CROSSREFS
| Cf. A053644.
Sequence in context: A179011 A134315 A119332 * A175917 A069971 A167291
Adjacent sequences: A089259 A089260 A089261 * A089263 A089264 A089265
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KEYWORD
| nonn,easy
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AUTHOR
| Ralf Stephan (ralf(AT)ark.in-berlin.de), Oct 30 2003
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