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A324007
Decimal expansion of the sum of reciprocals of the products of 3 consecutive Fibonacci numbers.
3
7, 1, 0, 8, 5, 5, 3, 5, 1, 4, 2, 9, 3, 2, 8, 4, 1, 6, 8, 8, 7, 6, 9, 4, 4, 9, 0, 3, 8, 4, 2, 7, 0, 8, 3, 3, 0, 4, 5, 1, 1, 8, 0, 4, 8, 4, 1, 0, 3, 0, 8, 6, 3, 9, 9, 7, 4, 9, 7, 3, 5, 1, 4, 9, 3, 6, 9, 6, 4, 2, 3, 8, 2, 6, 1, 1, 3, 5, 4, 4, 8, 4, 1, 7, 5, 8, 8, 4, 1, 6, 8, 1, 7, 1, 4, 8, 5, 8, 5, 7, 6, 8, 5, 4, 9
OFFSET
0,1
LINKS
Brother Alfred Brousseau, Summation of Infinite Fibonacci Series, The Fibonacci Quarterly, Vol. 7, No. 2 (1969), pp. 143-168.
R. S. Melham, On Some Reciprocal Sums of Brousseau: An Alternative Approach to That of Carlitz, Fibonacci Quarterly, Vol. 41, No. 1 (2003), pp. 59-62.
FORMULA
From Amiram Eldar, Feb 09 2023: (Start)
Equals Sum_{k>=1} 1/A065563(k).
Equals 1 - A158933 (Melham, 2003). (End)
EXAMPLE
0.71085535142932841688769449038427083304511804841030863997497351493696423826...
MATHEMATICA
RealDigits[ Sum[ N[ 1/Product[ Fibonacci@j, {j, k, k + 2}], 128], {k, 177}], 10, 111][[1]]
PROG
(PARI) suminf(n=1, 1/(fibonacci(n)*fibonacci(n+1)*fibonacci(n+2))) \\ Michel Marcus, Feb 19 2019
KEYWORD
nonn,cons
AUTHOR
Robert G. Wilson v, Feb 11 2019
STATUS
approved