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A119661 Maximum possible number of a pairwise elastic collisions in a dynamic system of 3 point masses m1,m2,m3 on a line, where m1 = n*m2 = m3. 0
3, 3, 4, 4, 5, 5, 6, 6, 6, 7, 7, 7, 8, 8, 8, 9, 9, 9, 9, 10, 10, 10, 10, 11, 11, 11, 11, 11, 12, 12, 12, 12, 12, 13, 13, 13, 13, 13, 14, 14, 14, 14, 14, 14, 15, 15, 15, 15, 15, 15, 15, 16, 16, 16, 16, 16, 16, 17, 17, 17, 17, 17, 17, 17, 18, 18, 18, 18, 18, 18, 18, 18, 19, 19, 19, 19 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(n) = N(m1,m2,m3) is independent of initial velocities and coordinates of masses m1,m2,m3. N(m1,m2,m3) = -IntegerPart[ -Pi/ArcCos[Sqrt[m1*m3/((m1+m2)*(m2+m3))]]].

REFERENCES

G. A. Galperin, A. N. Zemliakov, "Mathematical Billiards", "KVANT" Library, Issue 77, Moscow, Nauka, 1990, (in Russian). See p. 165.

LINKS

Table of n, a(n) for n=1..76.

G. A. Galperin, A. N. Zemliakov, "Mathematical Billiards" (in Russian)

FORMULA

a(n) = -IntegerPart[ -Pi/ArcCos[n/(n+1)]].

MATHEMATICA

Table[ -IntegerPart[ -Pi/ArcCos[n/(n+1)]], {n, 1, 100}]

CROSSREFS

Sequence in context: A075324 A134993 A011375 * A120196 A196179 A120188

Adjacent sequences:  A119658 A119659 A119660 * A119662 A119663 A119664

KEYWORD

nonn

AUTHOR

Alexander Adamchuk, Jul 28 2006

STATUS

approved

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Last modified May 18 07:10 EDT 2013. Contains 225419 sequences.