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A188724 Decimal expansion of shape of a (Pi/2)-extension rectangle; shape = (1/4)*(Pi + sqrt(16 + Pi^2). 1
2, 0, 5, 6, 9, 5, 2, 4, 3, 8, 7, 1, 0, 9, 6, 5, 9, 0, 9, 3, 9, 6, 7, 8, 7, 9, 2, 4, 3, 7, 8, 8, 0, 7, 2, 5, 8, 5, 8, 8, 0, 9, 9, 1, 4, 1, 5, 4, 9, 7, 1, 7, 6, 2, 0, 4, 6, 7, 6, 4, 2, 6, 8, 3, 4, 1, 6, 1, 9, 5, 6, 5, 7, 6, 0, 3, 4, 1, 7, 4, 6, 1, 3, 2, 2, 1, 8, 2, 6, 6, 1, 4, 5, 7, 6, 5, 0, 2, 1, 5, 1, 8, 9, 6, 9, 9, 2, 5, 3, 9, 6, 2, 4, 2, 1, 0, 6, 6, 2, 4, 8, 0, 9, 8, 2, 4, 8, 8, 4, 2 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

See A188640 for definitions of shape and r-extension rectangle. Briefly, an r-extension rectangle is composed of two rectangles of shape r.

A (Pi/2)-extension rectangle matches the continued fraction [2,17,1,1,3,1,3,2,2,1637,1,210,7,...] of the shape L/W = (1/4)*(Pi + sqrt(16 + Pi^2). This is analogous to the matching of a golden rectangle to the continued fraction [1,1,1,1,1,1,1,...]. Specifically, for the (Pi/2)-extension rectangle, 2 squares are removed first, then 17 squares, then 1 square, then 1 square, then 3 squares, ..., so that the original rectangle is partitioned into an infinite collection of squares.

LINKS

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

EXAMPLE

2.0569524387109659093967879243788072585880991...

MATHEMATICA

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

N[t, 130]

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

ContinuedFraction[t, 120]

CROSSREFS

Cf. A188640, A188722.

Sequence in context: A240657 A262420 A240662 * A082832 A334842 A320372

Adjacent sequences:  A188721 A188722 A188723 * A188725 A188726 A188727

KEYWORD

nonn,easy,cons

AUTHOR

Clark Kimberling, Apr 09 2011

STATUS

approved

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Last modified May 14 18:01 EDT 2021. Contains 343900 sequences. (Running on oeis4.)