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%I #13 May 03 2018 17:48:38
%S 1,3,3,27,3,9,3,27,27,9,3,81,3,9,9,7625597484987,3,81,3,81,9,9,3,81,
%T 27,9,27,81,3,27,3,27,9,9,9,729,3,9,9,81,3,27,3,81,81,9,3,
%U 22876792454961,27,81,9,81,3,81,9,81,9,9,3,243,3,9,81,19683,9,27,3,81
%N Multiplicative with a(p^k) = 3^a(k).
%C This sequence contains every power of 3; see A303823 for the corresponding least indices.
%C This sequence is a variant of A303809.
%H Rémy Sigrist, <a href="/A303822/b303822.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = n iff n = A014222(k) for some k > 0.
%F a(A002110(k)) = 3^k for any k >= 0.
%F a(n) = 3 iff n is prime.
%o (PARI) a(n) = my (f=factor(n)); prod (i=1, #f~, 3^a(f[i, 2]))
%Y Cf. A002110, A014222, A303809, A303823.
%K nonn,easy,mult
%O 1,2
%A _Rémy Sigrist_, May 01 2018