

A143264


A positive integer n is included if the binary representation of the number of divisors of n does not occur anywhere in the binary representation of n.


2



3, 4, 6, 7, 9, 10, 14, 15, 16, 18, 20, 21, 22, 26, 27, 30, 31, 32, 42, 46, 48, 54, 55, 58, 62, 63, 64, 68, 72, 75, 78, 84, 85, 86, 87, 90, 91, 93, 94, 95, 102, 105, 106, 110, 111, 112, 114, 118, 119, 120, 122, 123, 125, 126, 127, 132, 144, 147, 148, 150, 154, 160, 164
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OFFSET

1,1


LINKS

Table of n, a(n) for n=1..63.


EXAMPLE

30 has 8 divisors. 30 in binary is 11110. 8 in binary is 1000. The string 1000 does not occur anywhere in the string 11110. So 30 occurs in this sequence.


MATHEMATICA

bndQ[n_]:=Module[{bn=IntegerDigits[n, 2], dn=IntegerDigits[ DivisorSigma[ 0, n], 2]}, !MemberQ[ Partition[ bn, Length[dn], 1], dn]]; Select[Range[ 200], bndQ] (* Harvey P. Dale, Nov 01 2013 *)


CROSSREFS

Cf. A143262, A143263.
Sequence in context: A068675 A190858 A026315 * A126332 A039026 A123540
Adjacent sequences: A143261 A143262 A143263 * A143265 A143266 A143267


KEYWORD

base,nonn


AUTHOR

Leroy Quet, Aug 03 2008


EXTENSIONS

Extended by Ray Chandler, Nov 09 2008


STATUS

approved



