A158130 121n - 1.

120, 241, 362, 483, 604, 725, 846, 967, 1088, 1209, 1330, 1451, 1572, 1693, 1814, 1935, 2056, 2177, 2298, 2419, 2540, 2661, 2782, 2903, 3024, 3145, 3266, 3387, 3508, 3629, 3750, 3871, 3992, 4113, 4234, 4355, 4476, 4597, 4718, 4839, 4960, 5081, 5202

Offset

1,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..10000

Index entries for linear recurrences with constant coefficients, signature (2,-1).

Formula

a(n) = 2*a(n-1) -a(n-2).

G.f.: x*(120+x)/(x-1)^2.

Mathematica

Table[121n-1, {n, 50}]

Prog

(Magma) I:=[120, 241]; [n le 2 select I[n] else 2*Self(n-1)-Self(n-2): n in [1..50]];
(PARI) a(n) = 121*n - 1.

Crossrefs

Sequence in context: A232743 A146950 A028976 * A070856 A211467 A257712

Adjacent sequences: A158127 A158128 A158129 * A158131 A158132 A158133

Keyword

nonn,easy

Author

Vincenzo Librandi, Mar 13 2009

Status

approved