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Search: id:A085480
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| A085480 |
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a(n) = p^n + q^n, where p = (3 + sqrt 21)/2, q = (3 - sqrt 21)/2. |
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+0
2
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| 3, 15, 54, 207, 783, 2970, 11259, 42687, 161838, 613575
(list; graph; listen)
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OFFSET
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1,1
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COMMENT
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A Jacobsthal variation.
p - q = sqrt 21; pq = -3; p + q = 3.
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REFERENCES
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Thomas Koshy, "Fibonacci and Lucas Numbers with Applications", Wiley, 2001, p. 471.
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LINKS
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Tanya Khovanova, Recursive Sequences
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EXAMPLE
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a(4) = q^4 + q^4 = 207; p^5 + q^5 = 783, where p = (3 + sqrt 21)/2, q = (3 - sqrt 21)/2.
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CROSSREFS
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Cf. A030195.
Adjacent sequences: A085477 A085478 A085479 this_sequence A085481 A085482 A085483
Sequence in context: A043005 A118126 A038192 this_sequence A099581 A026696 A082708
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KEYWORD
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nonn
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AUTHOR
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Gary W. Adamson (qntmpkt(AT)yahoo.com), Jul 02 2003
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