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Decimal expansion of Sum_{k>=0} L(k)/k!, where L(k) is the k-th Lucas number (A000032).
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%I #16 Feb 06 2022 02:47:58

%S 5,5,8,2,1,6,8,7,2,6,0,8,4,0,7,3,2,7,2,2,7,3,8,2,0,0,8,7,6,5,0,1,0,1,

%T 0,8,0,6,7,9,7,0,8,6,8,2,2,5,7,9,4,8,5,3,9,5,2,2,8,4,1,8,5,0,0,5,3,2,

%U 6,4,7,8,7,7,1,3,7,6,1,1,7,0,8,0,7,6,2

%N Decimal expansion of Sum_{k>=0} L(k)/k!, where L(k) is the k-th Lucas number (A000032).

%D Thomas Koshy, Fibonacci and Lucas Numbers with Applications, Volume 1, 2nd edition, Wiley, 2017, chapter 13.8, pp. 248-250.

%F Equals exp(phi) + exp(1-phi), where phi is the golden ratio (A001622).

%F Equals e * A328495. - _Amiram Eldar_, Feb 06 2022

%e 5.582168726084073272273820087650101080679708682257948...

%t RealDigits[Exp[GoldenRatio] + Exp[1 - GoldenRatio], 10, 100][[1]]

%Y Cf. A000032, A001113, A001622, A098689, A139341, A139342, A328495.

%K nonn,cons

%O 1,1

%A _Amiram Eldar_, Oct 22 2019