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A121821 Decimal expansion of the Lucas binary number, Sum_{k>0} 1/2^L(k), where L(k) = A000032(k). 0
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 (list; constant; graph; refs; listen; history; text; internal format)
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

(PARI) suminf(n=1, 1/2^(fibonacci(n-1)+fibonacci(n+1))) \\ Charles R Greathouse IV, Nov 07 2014

CROSSREFS

Cf. A000032, A000045, A084119, A010056.

Sequence in context: A199445 A201297 A198818 * A021859 A196462 A242814

Adjacent sequences:  A121818 A121819 A121820 * A121822 A121823 A121824

KEYWORD

cons,nonn

AUTHOR

Alexander Adamchuk, Aug 26 2006

STATUS

approved

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Last modified December 20 07:03 EST 2014. Contains 252241 sequences.