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A235916
Decimal expansion of 3/sqrt(2*Pi).
1
1, 1, 9, 6, 8, 2, 6, 8, 4, 1, 2, 0, 4, 2, 9, 8, 0, 3, 3, 8, 1, 9, 8, 3, 8, 1, 7, 9, 8, 0, 3, 1, 4, 5, 6, 0, 5, 4, 2, 7, 5, 7, 5, 8, 9, 3, 4, 9, 4, 8, 0, 3, 9, 7, 2, 9, 9, 7, 7, 7, 7, 4, 8, 9, 0, 1, 1, 9, 7, 3, 7, 7, 7, 6, 9, 7, 9, 0, 5, 5, 1, 5, 5, 0, 3, 7, 5, 7, 0, 0, 1, 7, 2, 1, 9, 2, 0, 8, 0, 9, 2, 9, 0, 9, 0
OFFSET
1,3
COMMENTS
The radius of the large circle, the a-value in the MathWorld link, of a deltoid (3-cusped hypocycloid) with area 1. Thus, for any r > 0, this particular a*sqrt(r) is the radius of the large circle of a deltoid with area r. The radius of the small circle is a*sqrt(r)/3 = A231863*sqrt(r), because A231863 is the radius of the small circle, the b-value in the MathWorld link, of a deltoid with area 1.
FORMULA
3/sqrt(2*Pi) = 3/A019727 = 3*A231863 = 1/A019728.
EXAMPLE
1.1968268412042980338198381798031456054275758934948039729977774890119737...
MATHEMATICA
RealDigits[N[3/Sqrt[2Pi], 105]] [[1]]
PROG
(PARI) default(realprecision, 120); 3/sqrt(2*Pi)
(Magma) SetDefaultRealField(RealField(100)); R:= RealField(); 3/Sqrt(2*Pi(R)); // G. C. Greubel, Sep 30 2018
CROSSREFS
Cf. A019727, A019728, A231863 (corresponding small circle radius).
Sequence in context: A248472 A306553 A011194 * A198567 A021512 A154205
KEYWORD
nonn,cons
AUTHOR
Rick L. Shepherd, Jan 16 2014
STATUS
approved