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A189039 Decimal expansion of (Pi+sqrt(-4+Pi^2))/2. 2
2, 7, 8, 2, 1, 5, 9, 6, 4, 9, 7, 7, 9, 5, 1, 6, 1, 4, 9, 3, 1, 6, 0, 9, 7, 9, 9, 5, 8, 3, 1, 2, 8, 2, 8, 7, 1, 9, 4, 1, 9, 0, 6, 4, 7, 7, 7, 5, 6, 3, 3, 9, 3, 0, 4, 5, 3, 3, 9, 3, 2, 9, 8, 4, 1, 1, 8, 1, 6, 7, 9, 1, 9, 8, 3, 8, 4, 6, 9, 9, 2, 6, 5, 0, 6, 4, 4, 2, 4, 9, 2, 8, 7, 9, 0, 6, 7, 8, 8, 7, 6, 4, 2, 8, 9, 8, 7, 3, 3, 5, 7, 2, 7, 7, 9, 4, 2, 2, 5, 5, 4, 4, 7, 0, 7, 5, 2, 2, 1, 4 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Decimal expansion of the shape (= length/width = (Pi+sqrt(-4+Pi^2))/2) of the greater Pi-contraction rectangle.

See A188738 for an introduction to lesser and greater r-contraction rectangles, their shapes, and partitioning these rectangles into a sets of squares in a manner that matches the continued fractions of their shapes.

LINKS

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

EXAMPLE

2.78215964977951614931609799583128287194190...

MATHEMATICA

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

N[t, 130]

RealDigits[N[t, 130]][[1]] (*A189039*)

ContinuedFraction[t, 120]  (*A188804*)

PROG

(PARI) (Pi+sqrt(-4+Pi^2))/2 \\ Michel Marcus, Jun 14 2015

CROSSREFS

Cf. A188738, A188804.

Sequence in context: A086658 A272182 A175577 * A198815 A011053 A094216

Adjacent sequences:  A189036 A189037 A189038 * A189040 A189041 A189042

KEYWORD

nonn,cons

AUTHOR

Clark Kimberling, Apr 16 2011

STATUS

approved

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Last modified February 20 09:06 EST 2018. Contains 299384 sequences. (Running on oeis4.)