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A244094 Rounded down ratio of area of a unit circle and one of the  circles inscribed between a regular n-gon and a circumscribed unit circle. 5
16, 46, 109, 222, 407, 690, 1099, 1669, 2437, 3445, 4737, 6363, 8376, 10834, 13797, 17330, 21503, 26389, 32064, 38608, 46108, 54651, 64331, 75243, 87489, 101172, 116402, 133290, 151953, 172511, 195088, 219813, 246817, 276236, 308211, 342885, 380407, 420927, 464601, 511590 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,1

LINKS

Table of n, a(n) for n=3..42.

Kival Ngaokrajang, Illustration of initial terms

FORMULA

a(n) =  floor(Pi/area(n)) where area(n) =  Pi*r(n)^2, r(n) = (1 - cos(Pi/n))/2 = sin(Pi/(2*n))^2, n >= 3.

PROG

(PARI)

{

  for (n=3, 100,

     b=Pi*(n-2)/(2*n);

     r=(1-sin(b))/2;

     area=Pi*r^2;

     a=floor(Pi/area);

     print1(a, ", ")

  )

}

CROSSREFS

Cf. A244093, A244096.

Sequence in context: A069128 A099003 A124709 * A235549 A126370 A133345

Adjacent sequences:  A244091 A244092 A244093 * A244095 A244096 A244097

KEYWORD

nonn,easy

AUTHOR

Kival Ngaokrajang, Jun 20 2014

EXTENSIONS

Edited. Formula simplified - Wolfdieter Lang, Jun 27 2014

STATUS

approved

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Last modified January 19 17:59 EST 2020. Contains 331051 sequences. (Running on oeis4.)