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A174770
y-values in the solution to x^2 - 29*y^2 = 1.
2
0, 1820, 35675640, 699313893460, 13707950903927280, 268703252919468649100, 5267121150019473555730920, 103246108513978467719968844740, 2023830213823884774227355738862560
OFFSET
1,2
The corresponding values of x of this Pell equation are in A174769.
FORMULA
a(n) = 19602*a(n-1)-a(n-2) with a(1)=0, a(2)=1820.
G.f.: 1820*x^2/(1-19602*x+x^2).
MATHEMATICA
LinearRecurrence[{19602, -1}, {0, 1820}, 30]
Table[-((9801-1820*Sqrt[29])^x-(9801+1820*Sqrt[29])^x)/(2*Sqrt[29]), {x, 0, 10}]// Simplify (* Harvey P. Dale, Jul 02 2022 *)
PROG
(Magma) I:=[0, 1820]; [n le 2 select I[n] else 19602*Self(n-1)-Self(n-2): n in [1..20]];
CROSSREFS
Cf. A174769.
Sequence in context: A234660 A238030 A233719 * A218104 A171349 A256076
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Apr 14 2010
STATUS
approved

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Last modified September 20 13:10 EDT 2024. Contains 376072 sequences. (Running on oeis4.)