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A176453
Decimal expansion of 4+2*sqrt(5).
2
8, 4, 7, 2, 1, 3, 5, 9, 5, 4, 9, 9, 9, 5, 7, 9, 3, 9, 2, 8, 1, 8, 3, 4, 7, 3, 3, 7, 4, 6, 2, 5, 5, 2, 4, 7, 0, 8, 8, 1, 2, 3, 6, 7, 1, 9, 2, 2, 3, 0, 5, 1, 4, 4, 8, 5, 4, 1, 7, 9, 4, 4, 9, 0, 8, 2, 1, 0, 4, 1, 8, 5, 1, 2, 7, 5, 6, 0, 9, 7, 9, 8, 8, 2, 8, 8, 2, 8, 8, 1, 6, 7, 5, 7, 5, 6, 4, 5, 4, 9, 9, 3, 9, 0, 1
OFFSET
1,1
COMMENTS
Continued fraction expansion of 4+2*sqrt(5) is A010698 preceded by 8.
a(n) = A010476(n) = A020762(n-1) = A134974(n) for n > 1.
Rajan (2010) claims the variance of a discrete distribution generated by the linear convolution of Fibonacci sequence with itself, saturates to a constant of value 8.4721359. [From Jonathan Vos Post, May 10 2010]
LINKS
Arulalan Rajan, Jamadagni, Vittal Rao, Ashok Rao, Convolutions Induced Discrete Probability Distributions and a New Fibonacci Constant, May 6, 2010. [From Jonathan Vos Post, May 10 2010]
EXAMPLE
4+2*sqrt(5) = 8.47213595499957939281...
MATHEMATICA
RealDigits[4+2Sqrt[5], 10, 120][[1]] (* Harvey P. Dale, Sep 08 2018 *)
CROSSREFS
Cf. A002163 (decimal expansion of sqrt(5)), A010476 (decimal expansion of sqrt(20)), A020762 (decimal expansion of 1/sqrt(5)), A134974 (decimal expansion of 8/(1+sqrt(5))), A010698 (repeat 2, 8).
Sequence in context: A168546 A195346 A096427 * A257775 A242023 A249415
KEYWORD
cons,nonn
AUTHOR
Klaus Brockhaus, Apr 20 2010
STATUS
approved