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A097442 Integer part of the area of consecutive prime sided isosceles triangles. 0
2, 7, 16, 36, 64, 102, 144, 198, 306, 397, 520, 676, 774, 898, 1116, 1396, 1575, 1819, 2097, 2264, 2557, 2883, 3267, 3835, 4296, 4533, 4830, 5080, 5394, 6426, 7275, 7881, 8285, 9159, 9784, 10392, 11213, 11879, 12651, 13555, 14080, 15221, 16016, 16573 (list; graph; refs; listen; history; internal format)
OFFSET

2,1

COMMENTS

The real part of these numbers is always irrational.

FORMULA

Consider prime isosceles triangles of sides (2, 3, 3), (3, 5, 5), ..., (x, y, y) where x is prime and y is the next prime after x. Then area = 1/2*x*sqrt(y^2-(x/2)^2). Output floor(area)

PROG

(PARI) f(n) = forprime(x=2, n, y=nextprime(x+1); a=1/2*x*sqrt(y^2-(x/2)^2); print1(floor (a)", "))

CROSSREFS

Sequence in context: A023612 A192952 A132738 * A131405 A176805 A042243

Adjacent sequences:  A097439 A097440 A097441 * A097443 A097444 A097445

KEYWORD

nonn

AUTHOR

Cino Hilliard (hillcino368(AT)gmail.com), Aug 22 2004

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Last modified February 17 16:39 EST 2012. Contains 206058 sequences.