A103314 conjecture
David Wilson
davidwwilson at comcast.net
Thu May 19 21:22:39 CEST 2005
T. D. Noe wrote:
> a(3^n) = 2^(3^(n - 1))
> a(5^n) = 2^(5^(n - 1))
> a(6^n) = a(6)^(6^(n - 1)) = 10^(6^(n - 1))
>
> Tony
(where a(n) = A103314(n)).
These would all follow from my conjecture that
[1] a(n) = a(s(n))^(n/s(n))
where s(n) = A007947(n) is the squarefree kernel of n (product of primes
dividing n).
Now s(p^k) = p (k >= 1), so applying [1] gives
a(p^k) = a(p)^(p^(k-1)) (k >= 1)
But a(p) = 2 for prime p (have we proved this?), and so
a(p^k) = 2^p^(k-1).
Special cases p = 3 and p = 5 give your first two observations.
Similarly, s(6) = 6, and so [1] gives
a(6^k) = a(6)^6^(k-1)
as you observed. But a(pq) = 2^p+2^q-2, so a(6) = 10, giving
a(6^k) = 10^6^(k-1).
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