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A057672 a(n) equals floor(As(n) - Ac(n)), where As(n) is the area of the square with side length n and Ac(n) is the area of the circle of diameter n. 2
0, 0, 1, 3, 5, 7, 10, 13, 17, 21, 25, 30, 36, 42, 48, 54, 62, 69, 77, 85, 94, 103, 113, 123, 134, 145, 156, 168, 180, 193, 206, 219, 233, 248, 262, 278, 293, 309, 326, 343, 360, 378, 396, 415, 434, 454, 474, 494, 515, 536, 558, 580, 602, 625, 649, 672, 697, 721, 747, 772, 798 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Table of n, a(n) for n=1..61.

FORMULA

a(n) = floor(n^2*(1-Pi/4)).

EXAMPLE

a(7)=10 since floor(7^2(1-Pi/4)) = 10.

PROG

(PARI) a(n)=floor(n^2*(1-Pi/4)); \\ Michel Marcus, Sep 05 2014

CROSSREFS

Cf. A057671.

Sequence in context: A077000 A195311 A184013 * A112509 A173137 A212986

Adjacent sequences:  A057669 A057670 A057671 * A057673 A057674 A057675

KEYWORD

nonn

AUTHOR

seiringer.flor(AT)eudoramail.com, Oct 18 2000

EXTENSIONS

Edited and extended by James A. Sellers, Oct 20 2000

STATUS

approved

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Last modified October 24 14:22 EDT 2014. Contains 248516 sequences.