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A014013 Alternating Egyptian fraction expansion of Pi. +0
4
7, 790, 749896, 1270073831726, 3264508855407706377676178, 18710490702451568752627532846550947209438603938993, 97388599886622381202017650632887936515459526653688044906463960678560175438731104\ 7869879785998363014 (list; graph; listen)
OFFSET

1,1

LINKS

Index entries for sequences related to Egyptian fractions

FORMULA

pi-3 = sum(k>=1, (-1)^(k+1)/a(k)) = 0.14159...; a(n)=(-1)^(n+1)*u(n) where u(1)=7, u(n)=trunc(1/(Pi-3-sum(k=1, n-1, 1/u(k)))) and trunc(x)=floor(x) if x>=0, trunc(x)=ceil(x) if x<0

EXAMPLE

1/(Pi-3-1/7+1/790) = 749896.4427... hence a(3)=749896

CROSSREFS

Sequence in context: A114911 A162089 A020470 this_sequence A001467 A047788 A087350

Adjacent sequences: A014010 A014011 A014012 this_sequence A014014 A014015 A014016

KEYWORD

nonn

AUTHOR

Simon Plouffe (simon.plouffe(AT)gmail.com)

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Last modified November 30 13:13 EST 2009. Contains 167758 sequences.


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