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A174768
y-values in the solution to x^2 - 26*y^2 = 1.
3
0, 10, 1020, 104030, 10610040, 1082120050, 110365635060, 11256212656070, 1148023325284080, 117087122966320090, 11941738519239365100, 1217940241839448920110, 124217962929104550486120, 12669014278526824700664130, 1292115238446807014917255140, 131783085307295788696859360150
OFFSET
1,2
COMMENTS
The corresponding values of x of this Pell equation are in A099397.
FORMULA
a(n) = 102*a(n-1)-a(n-2) with a(1)=0, a(2)=10.
G.f.: 10*x^2/(1-102*x+x^2).
a(n+1) = A041041(2*n-1). - Michael Somos, Oct 25 2022
MATHEMATICA
LinearRecurrence[{102, -1}, {0, 10}, 30]
a[ n_] := Fibonacci[2*n-2, 10]; (* Michael Somos, Oct 25 2022 *)
PROG
(Magma) I:=[0, 10]; [n le 2 select I[n] else 102*Self(n-1)-Self(n-2): n in [1..20]];
CROSSREFS
Sequence in context: A127117 A154703 A172163 * A067104 A166507 A103623
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Apr 14 2010
STATUS
approved