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A157435
64n + 632.
3
696, 760, 824, 888, 952, 1016, 1080, 1144, 1208, 1272, 1336, 1400, 1464, 1528, 1592, 1656, 1720, 1784, 1848, 1912, 1976, 2040, 2104, 2168, 2232, 2296, 2360, 2424, 2488, 2552, 2616, 2680, 2744, 2808, 2872, 2936, 3000, 3064, 3128, 3192, 3256, 3320, 3384
OFFSET
1,1
COMMENTS
The identity (128*n^2+2528*n+12481)^2-(4*n^2+79*n+390)*(64*n+632)^2=1 can be written as A157436(n)^2-A157434(n)* a(n)^2=1.
FORMULA
a(n) = 2*a(n-1)-a(n-2).
G.f.: x*(696-632x)/(1-x)^2.
MATHEMATICA
LinearRecurrence[{2, -1}, {696, 760}, 50]
PROG
(Magma) I:=[696, 760]; [n le 2 select I[n] else 2*Self(n-1)-Self(n-2): n in [1..50]];
(PARI) a(n) = 64*n + 632.
CROSSREFS
Sequence in context: A048925 A251367 A221418 * A048426 A209731 A222782
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Mar 01 2009
STATUS
approved