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A095902
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Number of odd entries in A004001 that are <= 2^n.
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3
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1, 2, 2, 3, 6, 12, 27, 55, 115, 235, 490, 994, 2008, 4036, 8120, 16280, 32640, 65344, 130879, 261935, 524057, 1048301, 2096855, 4193951, 8388239, 16776799, 33554339, 67109539, 134220995
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OFFSET
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0,2
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COMMENTS
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Even entries and odd entries are equal only when n=4, 6 and 12. Past that, the evens outnumber the odds.
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LINKS
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FORMULA
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MATHEMATICA
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a[1] = a[2] = 1; a[n_] := a[n] = a[a[n - 1]] + a[n - a[n - 1]]; c = 0; k = 1; Do[ While[k <= 2^n, If[ Mod[ a[k], 2] == 1, c++ ]; k++ ]; Print[c], {n, 21}]
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PROG
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CROSSREFS
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KEYWORD
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more,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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