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A174766
y-values in the solution to x^2 - 22*y^2 = 1.
4
0, 42, 16548, 6519870, 2568812232, 1012105499538, 398766998005740, 157113185108762022, 61902196165854230928, 24389308176161458223610, 9609325519211448685871412, 3786049865261134620775112718
OFFSET
1,2
COMMENTS
The corresponding values of x of this Pell equation are in A114050.
FORMULA
a(n) = 394*a(n-1)-a(n-2) with a(1)=0, a(2)=42.
G.f.: 42*x^2/(1-394*x+x^2).
MATHEMATICA
LinearRecurrence[{394, -1}, {0, 42}, 30]
PROG
(Magma) I:=[0, 42]; [n le 2 select I[n] else 394*Self(n-1)-Self(n-2): n in [1..20]];
CROSSREFS
Cf. A114050.
Sequence in context: A268552 A227493 A095423 * A265191 A184895 A263058
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Apr 14 2010
STATUS
approved