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A158731
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a(n)=34*(34*n^2+1).
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1
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34, 1190, 4658, 10438, 18530, 28934, 41650, 56678, 74018, 93670, 115634, 139910, 166498, 195398, 226610, 260134, 295970, 334118, 374578, 417350, 462434, 509830, 559538, 611558, 665890, 722534, 781490, 842758, 906338, 972230, 1040434
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,1
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COMMENTS
| The identity (68*n^2+1)^2 - (1156*n^2+34) * (2*n)^2 = 1 can be written as
the Pell equation (A158732(n))^2 - a(n) * (A005843(n))^2 = 1.
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LINKS
| Vincenzo Librandi, X^2-AY^2=1
Edward Everett Withford, Pell Equation
Wolfram MathWorld, Pell Equation
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FORMULA
| a(n)= 3*a(n-1) -3*a(n-2) +a(n-3). G.f.: -34*(1+32*x+35*x^2)/(x-1)^3.
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CROSSREFS
| Cf. A005843, A158732
Sequence in context: A041545 A189434 A167258 * A093550 A123790 A202297
Adjacent sequences: A158728 A158729 A158730 * A158732 A158733 A158734
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KEYWORD
| nonn,easy
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AUTHOR
| Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Mar 25 2009
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EXTENSIONS
| Comment rewritten, a(0) added and formula replaced by R. J. Mathar, (mathar(AT)strw.leidenuniv.nl), Oct 22 2009
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