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A143262
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a(n) = the number of times the binary representation of the number of divisors of n occurs in the binary representation of n.
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3
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1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0, 0, 1, 1, 0, 0, 0, 1, 1, 1, 1, 2, 1, 1, 1, 2, 0, 2, 1, 1, 0, 1, 0, 1, 1, 1, 1, 2, 0, 0, 1, 1, 0, 1, 1, 1, 0, 0, 0, 1, 1, 1, 0, 1, 1, 1, 0, 2, 1, 0, 1, 1, 0, 1, 1, 1, 1, 2, 0, 0, 0, 0, 1, 2, 0, 0, 1, 0, 0, 0, 1, 1, 1, 1, 1, 2, 0, 1, 1, 0
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OFFSET
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1,37
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LINKS
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EXAMPLE
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37 has 2 divisors. 37 in binary is 100101. 2 in binary is 10. 10 occurs in two places in 100101: (10)0(10)1. So a(37) = 2.
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MATHEMATICA
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Table[SequenceCount[IntegerDigits[n, 2], IntegerDigits[DivisorSigma[0, n], 2]], {n, 110}] (* The program uses the SequenceCount function from Mathematica version 10.1 *) (* Harvey P. Dale, Apr 02 2015 *)
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CROSSREFS
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KEYWORD
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base,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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