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Number of divisors of n that are prefixes of other divisors of n in binary representation.

1

`%I #4 Mar 30 2012 18:50:42
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`%S 0,1,1,2,1,2,1,3,1,3,1,4,1,2,2,4,1,4,1,4,2,3,1,6,1,2,2,4,1,5,1,5,1,3,
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`%T 1,7,1,3,2,6,1,5,1,4,3,3,1,8,1,4,2,4,1,6,2,6,2,2,1,8,1,2,3,6,1,5,1,5,
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`%U 1,5,1,9,1,3,2,5,1,6,1,8,2,3,1,8,2,3,2,6,1,7,1,4,2,3,2,10,1,3,2,6,1,6
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`%N Number of divisors of n that are prefixes of other divisors of n in binary representation.
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`%C a(p) = 1 for all primes p;
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`%C a(n) = A090330(n) + 1.
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`%e Divisors of n=35: {1,5,7,35}, in binary {1,101,111,100011}: as
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`%e only '1' is a prefex, a(35)=1;
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`%e divisors of n=45: {1,3,5,9,15,45}, in binary
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`%e {1,11,101,1001,1111,101101}: '1' is a prefex of all other divisors, '11' of
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`%e '1111' and '101' of '101101', therefore a(45)=3.
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`%Y Cf. A000005.
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`%K nonn
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`%O 1,4
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`%A _Reinhard Zumkeller_, Nov 26 2003
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