[seqfan] Re: definition of A216677 (sq's dividing prod. of divs of n)

[Jonathan Stauduhar]

His examples are confusing, but rewriting his comment make it clear:

Ex.
n=6
divisors of 6 = {1,2,3,6}
products of divisors (with multiplicity) {1*1, 1*2, 1*3, 1*6, 2*3, 2*6, 3*6, 6*6} = {1,2,3,6,6,12,18,36} ->  (no multiplicity) {1,2,3,6,12,18,36}
squares in {1,2,3,6,12,18,36} are 1*1 and  6*6.
do not count the trivial solution 1
Thus a(6)=1

So,

a(n) = the number of squares contained in the set of combinations of the products of the divisors of n.

...or words to that affect...I think.

Jonathan

On 9/18/2012 1:18 AM, mathar wrote:
> Can anybody decipher what the actual definition of
> http://oeis.org/A216677 might be? This counts squares
> which divide the product of all divisors of n (sounds
> trivial) but seems to reject squares which miss
> some sort of criterion (to be defined). The criterion is
> probably related to a request that all squares need to have
> a set of divisors which encompasses at least the prime divisors of n.
>
> Some email exchange with the author did not yield much progress
> on the theme.
>