Interesting problem: A076109

[David Wilson]

One of Mitchell Harris's potentially multplicative sequences is A076109.

It appears to me that A076109 is multplicative with

    a(p^e) =
        1    if p = 2, e = 1,
        0    if p = 2, e > 1,
        p    if p >= 3.

(under the usual assumption p prime, e >= 1).

This, i believe, leads to the formula

    a(n) =
        0                          if n == 0 (mod 4)
        A007947(n)/2    if n == 2 (mod 4)
        A007947(n)       if n == 1 (mod 2)

The problem is to show that the sequence definition is equivalent to one of 
these characterizations.


- David W. Wilson

"Truth is just truth -- You can't have opinions about the truth."
   - Peter Schickele, from P.D.Q. Bach's oratorio "The Seasonings"