A121821 - OEIS

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A121821

Decimal expansion of the Lucas binary number, Sum_{k>0} 1/2^L(k), where L(k) = A000032(k).

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

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OFFSET

0,1

COMMENTS

Its binary expansion is equal to 1 if n is Lucas number else 0.

LINKS

Table of n, a(n) for n=0..104.

EXAMPLE

0.6958045978099178796583278671416595597...

MATHEMATICA

RealDigits[N[Sum[1/2^(Fibonacci[k-1]+Fibonacci[k+1]), {k, 1, 20}], 150]]

PROG