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A243112
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a(n) is the smallest number that requires at least n adjacent bit swaps in order to pack all the ones to the right.
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1
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0, 2, 4, 8, 12, 20, 24, 40, 48, 56, 88, 104, 112, 176, 208, 224, 240, 368, 432, 464, 480, 736, 864, 928, 960, 992, 1504, 1760, 1888, 1952, 1984, 3008, 3520, 3776, 3904, 3968, 4032, 6080, 7104, 7616, 7872, 8000, 8064, 12160, 14208, 15232, 15744, 16000, 16128
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OFFSET
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0,2
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COMMENTS
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a(n) = i if and only if A055941(i) == n and A055941(j) < n for all j < i.
Indices where records of A055941 occur.
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LINKS
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PROG
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(PARI) a055941(n) = {my(b=binary(n)); nb = 0; for (i=1, #b-1, if (b[i], nb += sum(j=i+1, #b, !b[j])); ); nb; }
lista(nn) = {vmax = 0; print1(vmax, ", "); for (n=1, nn, vnew = a055941(n); if (vnew > vmax, vmax = vnew; print1(n, ", "); ); ); } \\ Michel Marcus, Aug 29 2014
(Python)
for n in range(1, 2**30):
....s = bin(n)[2:]
....b = sum(s[i:].count('0') for i, d in enumerate(s, start=1) if d == '1')
....if b > a:
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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