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Search: id:A062882
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| A062882 |
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(1-2*cos(1/9*Pi))^n+(1+2*cos(2/9*Pi))^n+(1+2*cos(4/9*Pi))^n. |
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+0
2
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| 3, 9, 18, 45, 108, 270, 675, 1701, 4293, 10854, 27459, 69498, 175932, 445419, 1127763, 2855493, 7230222, 18307377, 46355652, 117376290, 297206739, 752553261, 1905530913, 4824972522, 12217257783, 30935180610, 78330624264
(list; graph; listen)
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OFFSET
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1,1
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LINKS
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Harry J. Smith, Table of n, a(n) for n=1,...,200
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FORMULA
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G.f.: (3x-9x^3)/(1-3x-3x^3). The terms in parentheses in the definition are the roots of 1-3x-3x^3. - Ralf Stephan, Apr 10 2004
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MAPLE
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Digits := 1000:q := seq(floor(evalf((1-2*cos(1/9*Pi))^n+(1+2*cos(2/9*Pi))^n+(1+2*cos(4/9*Pi))^n)), n=1..50);
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PROGRAM
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(PARI) { default(realprecision, 200); for (n=1, 200, a=(1 - 2*cos(1/9*Pi))^n + (1 + 2*cos(2/9*Pi))^n + (1 + 2*cos(4/9*Pi))^n; write("b062882.txt", n, " ", round(a)) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Aug 12 2009]
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CROSSREFS
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Cf. A033304, A062883.
Sequence in context: A028723 A057578 A015635 this_sequence A027101 A015656 A056372
Adjacent sequences: A062879 A062880 A062881 this_sequence A062883 A062884 A062885
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KEYWORD
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easy,nonn
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AUTHOR
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Vladeta Jovovic (vladeta(AT)eunet.rs), Jun 27 2001
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EXTENSIONS
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More terms from Sascha Kurz (sascha.kurz(AT)uni-bayreuth.de), Mar 24 2002
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