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A130261
Partial sums of the 'lower' even Fibonacci Inverse A130259.
10
0, 1, 2, 4, 6, 8, 10, 12, 15, 18, 21, 24, 27, 30, 33, 36, 39, 42, 45, 48, 51, 55, 59, 63, 67, 71, 75, 79, 83, 87, 91, 95, 99, 103, 107, 111, 115, 119, 123, 127, 131, 135, 139, 143, 147, 151, 155, 159, 163, 167, 171, 175, 179, 183, 187, 192, 197, 202, 207, 212, 217
OFFSET
0,3
LINKS
FORMULA
a(n) = (n+1)*A130259(n) - A001519(A130259(n)+1) + 1.
a(n) = (n+1)*A130259(n) - Fib(2*A130259(n)+1) + 1.
G.f.: g(x) = 1/(1-x)^2*Sum_{k>=1} x^Fib(2*k).
MATHEMATICA
Table[Sum[Floor[1/2*Log[GoldenRatio, (Sqrt[5]*k + 1)]], {k, 0, n}], {n, 0, 50}] (* G. C. Greubel, Sep 12 2018 *)
PROG
(PARI) for(n=0, 50, print1(sum(k=0, n, floor(log((sqrt(5)*k+1))/(2*log((1 +sqrt(5))/2)))), ", ")) \\ G. C. Greubel, Sep 12 2018
(Magma) [(&+[Floor(Log((Sqrt(5)*k+1))/(2*Log((1+Sqrt(5))/2))): k in [0..n]]): n in [0..50]]; // G. C. Greubel, Sep 12 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
Hieronymus Fischer, May 25 2007
STATUS
approved