

A090335


Smallest number with exactly n distinct prime factors such that in binary representation the divisors >1 form a prefix code.


2




OFFSET

1,2


COMMENTS

a(n) = Min{k: A090330(k)=0 and A001221(k)=n};
Conjecture: the sequence is defined for all n.
a(10) <= 281594003343201014885689.  David Wasserman, Dec 13 2005


LINKS

Table of n, a(n) for n=1..10.


EXAMPLE

a(3) = 2093 = 7*13*23 with divisors >1: 7, 13, 23, 91, 161, 299 and 2093, which are prefixfree in binary: 111, 1101, 10111, 1011011, 10100001, 100101011 and 100000101101.


CROSSREFS

Cf. A088862, A090332.
Sequence in context: A242621 A206385 A263052 * A302452 A113105 A132567
Adjacent sequences: A090332 A090333 A090334 * A090336 A090337 A090338


KEYWORD

nonn


AUTHOR

Reinhard Zumkeller, Nov 26 2003


EXTENSIONS

More terms from David Wasserman, Dec 13 2005


STATUS

approved



