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A175672
y-values in the solution to x^2 - 28*y^2=1.
3
0, 24, 6096, 1548360, 393277344, 99890897016, 25371894564720, 6444361328541864, 1636842405555068736, 415751526649658917080, 105599250926607809869584, 26821793983831734047957256
OFFSET
1,2
COMMENTS
The corresponding values of x of this Pell equation are in A175633.
FORMULA
a(n) = 254*a(n-1)-a(n-2) with a(1)=0, a(2)=24.
G.f.: 24*x^2/(1-254*x+x^2).
MATHEMATICA
LinearRecurrence[{254, -1}, {0, 24}, 20]
PROG
(Magma) I:=[0, 24]; [n le 2 select I[n] else 254*Self(n-1)-Self(n-2): n in [1..15]];
CROSSREFS
Cf. A175633.
Sequence in context: A277001 A163576 A145408 * A181749 A266312 A181232
KEYWORD
nonn,easy,less
AUTHOR
Vincenzo Librandi, Dec 04 2010
STATUS
approved