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Search: id:A132596
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| A132596 |
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Sequence allows us to find X values of the equation: X(X + 1) - 6*Y^2 = 0. |
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+0 2
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| 0, 2, 24, 242, 2400, 23762, 235224, 2328482, 23049600, 228167522, 2258625624, 22358088722, 221322261600, 2190864527282, 21687323011224, 214682365584962, 2125136332838400, 21036680962799042, 208241673295152024
(list; graph; listen)
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OFFSET
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0,2
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COMMENT
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Or, 3*A000217(X) is a square. [From Zak Seidov (zakseidov(AT)yahoo.com), Apr 08 2009]
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FORMULA
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a(0)=0, a(1)=2 and a(n)=10*a(n-1) - a(n-2) + 4.
a(n)=-1/2+(1/4)*[5+2*sqrt(6)]^n+(1/4)*[5-2*sqrt(6)]^n, with n>=0 - Paolo P. Lava (ppl(AT)spl.at), Jul 15 2008
a(n) = (A001079(n) - 1)/2 [From Max Alekseyev (maxale(AT)gmail.com), Nov 13 2009]
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CROSSREFS
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Cf. A007654.
Sequence in context: A147538 A025131 A143407 this_sequence A099669 A019520 A061190
Adjacent sequences: A132593 A132594 A132595 this_sequence A132597 A132598 A132599
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KEYWORD
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nonn
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AUTHOR
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Mohamed Bouhamida (bhmd95(AT)yahoo.fr), Nov 14 2007
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EXTENSIONS
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More terms from Max Alekseyev (maxale(AT)gmail.com), Nov 13 2009
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