OFFSET
1,1
LINKS
Paolo Xausa, Table of n, a(n) for n = 1..1000
Index entries for linear recurrences with constant coefficients, signature (11,-10).
FORMULA
a(n) = (2*10^n + 10)/15. - Robert Gerbicz, Sep 06 2002
From Alois P. Heinz, Sep 26 2021: (Start)
G.f.: 2*x*(1 - 4*x)/((1 - x)*(1 - 10*x)).
a(n) = 2 * A067275(n). (End)
From Elmo R. Oliveira, Aug 26 2024: (Start)
E.g.f.: (2*exp(x)*(exp(9*x) + 5) - 12)/15.
a(n) = 11*a(n-1) - 10*a(n-2) for n > 2. (End)
EXAMPLE
a(2) = 14 because there are 14 Fibonacci numbers up to Fibonacci(10^2) = 354224848179261915075 which end in 5.
MATHEMATICA
(2*10^Range[25] + 10)/15 (* Paolo Xausa, Jul 29 2026 *)
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Shyam Sunder Gupta, Aug 15 2002
EXTENSIONS
More terms from Robert Gerbicz, Sep 06 2002
Example clarified by Harvey P. Dale, Sep 26 2021
STATUS
approved