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A038756
Earliest sequence where a(a(n))=3^n.
2
2, 3, 9, 5, 81, 7, 729, 10, 27, 6561, 12, 177147, 14, 1594323, 16, 14348907, 18, 129140163, 20, 1162261467, 22, 10460353203, 24, 94143178827, 26, 847288609443, 19683, 29, 22876792454961, 31, 205891132094649, 33, 1853020188851841, 35
OFFSET
1,1
EXAMPLE
a(7)=a(a(6))=3^6=729
CROSSREFS
Sequence in context: A109607 A324581 A127612 * A011164 A082234 A263256
KEYWORD
nonn
AUTHOR
Henry Bottomley, May 03 2000
STATUS
approved