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A165421 a(1) = 1, a(2) = 3, a(n) = product of the previous terms for n >= 3. 5
1, 3, 3, 9, 81, 6561, 43046721, 1853020188851841, 3433683820292512484657849089281, 11790184577738583171520872861412518665678211592275841109096961 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Essentially a duplicate of A011764. - N. J. A. Sloane, Oct 06 2009

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..14

FORMULA

a(1) = 1, a(2) = 3, a(n) = product_{i=1..n-1} a(i), n >= 3. a(1) = 1, a(2) = 3, a(n) = A000244(2^(n-3)) = A011764(n-3) = 3^(2^(n-3)), n >= 3. a(1) = 1, a(2) = 3, a(3) = 3, a(n) = (a(n-1))^2, n >= 4.

CROSSREFS

Sequence in context: A257627 A115564 A122961 * A227432 A100731 A072004

Adjacent sequences:  A165418 A165419 A165420 * A165422 A165423 A165424

KEYWORD

nonn

AUTHOR

Jaroslav Krizek, Sep 17 2009

STATUS

approved

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Last modified November 23 20:23 EST 2017. Contains 295141 sequences.