A097426 - OEIS

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A097426

Integer part of the circumference of circles with prime diameters.

6, 9, 15, 21, 34, 40, 53, 59, 72, 91, 97, 116, 128, 135, 147, 166, 185, 191, 210, 223, 229, 248, 260, 279, 304, 317, 323, 336, 342, 354, 398, 411, 430, 436, 468, 474, 493, 512, 524, 543, 562, 568, 600, 606, 618, 625, 662, 700, 713, 719, 731, 750, 757, 788, 807

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Table of n, a(n) for n=1..55.

FORMULA

Circumference = Pi*D.

EXAMPLE

If D = 11. floor(Pi*11) = 34, the fifth entry.

MAPLE

seq(floor(ithprime(i)*Pi), i=1..100); # Robert Israel, Feb 09 2015

MATHEMATICA