

A081393


a(n) is the smallest x such that number of nonunitary prime divisors of central binomial coefficient, A000984(x)=C(2x,x) equals n.


2



1, 3, 5, 14, 48, 74, 182, 314, 480, 774, 960, 1321, 1323, 1670, 3121, 3455, 3457, 3472, 3462, 3469, 8203, 9991
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OFFSET

0,2


LINKS

Table of n, a(n) for n=0..21.


FORMULA

a(n) = Min{x; A081387(x)=n}.


EXAMPLE

n=5: a(5)=74, C(148,74) has 5 nonunitary prime divisors: {2,3,5,7,11} and 74 is the smallest.


CROSSREFS

Cf. A081387, A081394, A081395.
Sequence in context: A230585 A006395 A078718 * A338368 A129326 A167553
Adjacent sequences: A081390 A081391 A081392 * A081394 A081395 A081396


KEYWORD

nonn,more


AUTHOR

Labos Elemer, Mar 27 2003


EXTENSIONS

a(11)a(21) from Michel Marcus, Sep 01 2019


STATUS

approved



