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A135246
Shifted Pell recurrence: a(n) = 2*a(n-2) + a(n-4).
1
1, 3, 5, 7, 11, 17, 27, 41, 65, 99, 157, 239, 379, 577, 915, 1393, 2209, 3363, 5333, 8119, 12875, 19601, 31083, 47321, 75041, 114243, 181165, 275807, 437371, 665857, 1055907, 1607521, 2549185, 3880899, 6154277, 9369319, 14857739, 22619537, 35869755, 54608393, 86597249, 131836323, 209064253, 318281039, 504725755, 768398401, 1218515763, 1855077841, 2941757281, 4478554083
OFFSET
0,2
COMMENTS
Mix A048655(n) and A001333(n+2).
FORMULA
G.f.: (1 + 3*x + 3*x^2 + x^3)/(1 - 2*x^2 - x^4). - G. C. Greubel, Oct 04 2016
a(n) = 2*a(n-2) + a(n-4). - Wesley Ivan Hurt, Dec 30 2023
MATHEMATICA
LinearRecurrence[{0, 2, 0, 1}, {1, 3, 5, 7}, 25] (* G. C. Greubel, Oct 04 2016 *)
PROG
(PARI) Vec((1 + 3*x + 3*x^2 + x^3)/(1 - 2*x^2 - x^4) + O(x^50)) \\ Michel Marcus, Oct 05 2016
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Paul Curtz, Feb 15 2008
STATUS
approved