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a(n) is the smallest positive integer k such that A002325(k) = n.
1

%I #25 Jul 03 2024 13:06:15

%S 1,3,9,27,81,99,729,297,1089,891,59049,1683,531441,8019,9801,5049,

%T 43046721,18513,387420489,15147,88209,649539,31381059609,31977,

%U 1185921,5845851,314721,136323,22876792454961,166617,205891132094649,95931,7144929,473513931,10673289,351747,150094635296999121

%N a(n) is the smallest positive integer k such that A002325(k) = n.

%F If p is prime, a(p) = 3^(p-1).

%F a(n) is divisible by 3 for n > 1.

%e n | a(n)

%e -----+-----------------------

%e 2 | 3.

%e 3 | 9 = 3^2.

%e 4 | 27 = 3^3.

%e 5 | 81 = 3^4.

%e 6 | 99 = 3^2 * 11.

%e 7 | 729 = 3^6.

%e 8 | 297 = 3^3 * 11.

%e 9 | 1089 = 3^2 * 11^2.

%e 10 | 891 = 3^4 * 11.

%e 11 | 59049 = 3^10.

%e 12 | 1683 = 3^2 * 11 * 17.

%Y Cf. A002325, A033715, A033200, A200977, A374295.

%K nonn

%O 1,2

%A _Seiichi Manyama_, Jul 02 2024