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A152007
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Numbers of the form (2^EulerPhi[3^n]-1)/3^n.
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1
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OFFSET
| 1,3
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COMMENTS
| The next term is too large to display.
With the exception of 7 there are no primes in this sequence.
All numbers in this sequence are squarefree.
a(n) is divisible by a(k) for every k < n.
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MATHEMATICA
| Table[(2^EulerPhi[3^n] - 1)/3^n, {n, 0, 10}]
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CROSSREFS
| Cf. A008776, A152008.
Sequence in context: A116631 A074489 A067248 * A131676 A203685 A134645
Adjacent sequences: A152004 A152005 A152006 * A152008 A152009 A152010
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KEYWORD
| nonn
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AUTHOR
| Artur Jasinski (grafix(AT)csl.pl), Nov 19 2008
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EXTENSIONS
| Edited by N. J. A. Sloane (njas(AT)research.att.com), Nov 28 2008
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