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A093050
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Exponent of 2 in (3^n-3)*2^(n-1).
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2
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0, 0, 3, 2, 6, 4, 7, 6, 11, 8, 11, 10, 14, 12, 15, 14, 20, 16, 19, 18, 22, 20, 23, 22, 27, 24, 27, 26, 30, 28, 31, 30, 37, 32, 35, 34, 38, 36, 39, 38, 43, 40, 43, 42, 46, 44, 47, 46, 52, 48, 51, 50, 54, 52, 55, 54, 59, 56, 59, 58, 62, 60, 63, 62, 70, 64, 67, 66, 70
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OFFSET
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0,3
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LINKS
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FORMULA
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Recurrence: a(2n) = a(n) + [(n+1)/2] + 1, a(2n+1) = 2n.
G.f.: sum(k>=0, t^2(3+2t+2t^3-t^4)/[(1+t^2)(1-t^2)^2], t=x^2^k).
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PROG
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(PARI) a(n)=if(n<1, 0, if(n%2==0, a(n/2)+2*floor((n+2)/4)+1, n-1)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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