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A188883 Decimal expansion of (1+sqrt(1+pi^2))/pi. 1
1, 3, 6, 7, 7, 4, 8, 3, 9, 4, 9, 3, 1, 3, 6, 7, 4, 4, 4, 6, 9, 9, 6, 9, 1, 7, 6, 5, 6, 8, 2, 2, 0, 5, 4, 5, 5, 6, 5, 1, 1, 1, 3, 2, 6, 8, 9, 0, 2, 1, 4, 8, 8, 6, 9, 4, 7, 5, 0, 0, 4, 6, 5, 7, 5, 6, 7, 1, 5, 3, 4, 5, 6, 2, 8, 2, 0, 1, 7, 6, 9, 3, 0, 7, 9, 0, 1, 9, 3, 0, 9, 7, 4, 1, 9, 3, 2, 3, 3, 5, 3, 1, 2, 2, 6, 6, 3, 0, 2, 7, 3, 4, 3, 3, 0, 8, 1, 4, 5, 9, 8, 2, 2, 8, 1, 5, 8, 9, 1, 9 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Decimal expansion of the length/width ratio of a (2/pi)-extension rectangle.  See A188640 for definitions of shape and r-extension rectangle.

A (2/pi)-extension rectangle matches the continued fraction [1,2,1,2,1,1,3,1,1,5,1,7,1,1,23,2,...] for the shape L/W=(1+sqrt(1+pi^2))/pi.  This is analogous to the matching of a golden rectangle to the continued fraction [1,1,1,1,1,1,1,1,...].  Specifically, for the (2/pi)-extension rectangle, 1 square is removed first, then 2 squares, then 1 square, then 2 squares,..., so that the original rectangle of shape (1+sqrt(1+pi^2))/pi is partitioned into an infinite collection of squares.

LINKS

Table of n, a(n) for n=1..130.

EXAMPLE

1.36774839493136744469969176568220545565111326890

MATHEMATICA

r = 2/Pi; t = (r + (4 + r^2)^(1/2))/2; FullSimplify[t]

N[t, 130]

RealDigits[N[t, 130]][[1]]

ContinuedFraction[t, 120]

CROSSREFS

Cf. A188640, A188884, A188724, A188726.

Sequence in context: A290943 A067753 A129023 * A152083 A251532 A251533

Adjacent sequences:  A188880 A188881 A188882 * A188884 A188885 A188886

KEYWORD

nonn,cons

AUTHOR

Clark Kimberling, Apr 12 2011

STATUS

approved

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Last modified February 23 07:45 EST 2018. Contains 299473 sequences. (Running on oeis4.)