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A350678
Partial sums of A185381.
1
0, 1, 3, 6, 14, 35, 69, 158, 302, 679, 1666, 3263, 7444, 18390, 36101, 82469, 157494, 353912, 868141, 1700181, 3878490, 7403068, 16630533, 40788350, 79876519, 182210674, 450124970, 883619407, 2018522577, 3854834480, 8662361456, 21248630481, 41613641555, 94929932728, 234513795173
OFFSET
0,3
LINKS
Martin Griffiths, The Zeckendorf Representation of a Beatty-Related Fibonacci Sum, Fibonacci Quart. 53 (2015), no. 3, 230-236.
FORMULA
a(n) = Sum_{k=1..n} A185381(k).
MATHEMATICA
f[n_] := Fibonacci[Floor[GoldenRatio * n]]; Accumulate @ Array[f, 35, 0] (* Amiram Eldar, Jan 11 2022 *)
PROG
(PARI) B(n) = (n+sqrtint(5*n^2))\2; \\ A000201
f(n) = fibonacci(B(n)); \\ A185381
a(n) = sum(k=1, n, f(k));
(Python)
from math import isqrt
from sympy import fibonacci
def A350678(n): return sum(fibonacci((i+isqrt(5*i**2))//2) for i in range(n+1)) # Chai Wah Wu, Jan 11 2022
CROSSREFS
KEYWORD
nonn
AUTHOR
Michel Marcus, Jan 11 2022
STATUS
approved