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A255913 Decimal expansion of A such that y = A*x^2 cuts the first quadrant of the unit circle into two equal areas. 0
2, 3, 5, 2, 2, 3, 0, 1, 5, 3, 9, 1, 5, 8, 0, 7, 6, 3, 4, 8, 5, 2, 7, 7, 2, 5, 1, 2, 1, 1, 7, 5, 4, 1, 5, 8, 0, 7, 3, 9, 2, 1, 5, 4, 2, 4, 8, 8, 0, 2, 4, 3, 0, 8, 9, 2, 3, 5, 7, 8, 2, 9, 7, 7, 4, 2, 8, 1, 3, 7, 8, 6, 8, 5, 9, 3, 7, 7, 0, 4, 8, 9, 3, 4, 0, 0, 4, 6, 7, 7, 6, 4, 0, 0, 0, 9, 4, 9, 8, 3, 6, 4, 7, 1, 4, 2, 4, 1 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A is found by solving the equation A*x^3/3 = Pi/4 - arcsin(x), where x = sqrt( (sqrt(4*A^2+1)-1)/(2*A^2) ).

LINKS

Table of n, a(n) for n=1..108.

EXAMPLE

2.352230153915807634852772512117541580739215424880243089235782...

PROG

(PARI) solve(A = 2, 3, A/3*(sqrt((sqrt(4*A^2+1)-1)/(2*A^2)))^3 - Pi/4 + asin(sqrt((sqrt(4*A^2+1)-1)/(2*A^2)))) \\ Michel Marcus, Mar 11 2015

CROSSREFS

Sequence in context: A011157 A205387 A060441 * A065996 A133906 A317358

Adjacent sequences:  A255910 A255911 A255912 * A255914 A255915 A255916

KEYWORD

nonn,cons,easy

AUTHOR

Derek Orr, Mar 10 2015

STATUS

approved

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Last modified August 12 23:19 EDT 2020. Contains 336440 sequences. (Running on oeis4.)