login
A120727
a(n) = a(n-1) + a(n-2), starting with 110, 211.
1
110, 211, 321, 532, 853, 1385, 2238, 3623, 5861, 9484, 15345, 24829, 40174, 65003, 105177, 170180, 275357, 445537, 720894, 1166431, 1887325, 3053756, 4941081, 7994837, 12935918, 20930755, 33866673, 54797428, 88664101, 143461529
OFFSET
1,1
FORMULA
a(0)=101, a(1)=110, a(n) = a(n-1) + a(n-2).
G.f.: (110*x + 101*x^2)/(1 - x - x^2). - Philippe Deléham, Nov 20 2008
MATHEMATICA
d = 10 M = {{0, 1, 0}, {0, 0, 1}, {1, d, d^2}} v[n_] := Table[Fibonacci[n + i], {i, 0, 2}] w[n_] := M.v[n] Table[w[n][[3]], {n, 0, 50}]
Transpose[NestList[Flatten[{Last[#], Total[#]}]&, {110, 211}, 40]][[1]] (* or *) Rest[CoefficientList[Series[(110x+101x^2)/(1-x-x^2), {x, 0, 41}], x]] (* Harvey P. Dale, Mar 27 2011 *)
LinearRecurrence[{1, 1}, {110, 211}, 30] (* Harvey P. Dale, Jan 01 2023 *)
PROG
(Magma) [n le 2 select 101*n+9 else Self(n-1)+Self(n-2): n in [1..30]] // Bruno Berselli, Mar 28 2011
(PARI) a=vector(99); a[1]=110; a[2]=211; for(i=3, #a, a[i]=a[i-1]+a[i-2]); a \\ Charles R Greathouse IV, Jun 05 2011
CROSSREFS
Cf. A000045.
Sequence in context: A249838 A103652 A032614 * A251230 A264447 A134213
KEYWORD
nonn,easy
AUTHOR
Roger L. Bagula, Aug 19 2006
EXTENSIONS
Edited by N. J. A. Sloane, Dec 04 2006
STATUS
approved