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A087276
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Write n in binary: 1ab..yz, then a(n) = 1ab..yz + ... + 1yz + 1z + 1.
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1
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1, 3, 4, 7, 9, 9, 11, 15, 18, 19, 22, 19, 22, 23, 26, 31, 35, 37, 41, 39, 43, 45, 49, 39, 43, 45, 49, 47, 51, 53, 57, 63, 68, 71, 76, 75, 80, 83, 88, 79, 84, 87, 92, 91, 96, 99, 104, 79, 84, 87, 92, 91, 96, 99, 104, 95, 100, 103, 108, 107, 112, 115
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,2
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COMMENTS
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LINKS
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FORMULA
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a(1) = 1, a(2n) = 2a(n) + 1, a(2n+1) = 2*a(n) + floor(log_2(n)) + 2.
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PROG
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(PARI) a(n)=local(v, s, l); v=binary(n); l=length(v); s=0; for(k=2, l, s=s+2^(l-k)+sum(m=k+1, l, v[m]*2^(l-m))); s+n
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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