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Search: id:A097442
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| A097442 |
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Integer part of the area of consecutive prime sided isosceles triangles. |
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+0
1
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| 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; listen)
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OFFSET
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2,1
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COMMENT
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The real part of these numbers is always irrational.
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FORMULA
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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)
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PROGRAM
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(PARI) f(n) = forprime(x=2, n, y=nextprime(x+1); a=1/2*x*sqrt(y^2-(x/2)^2); print1(floor (a)", "))
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CROSSREFS
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Sequence in context: A130869 A023612 A132738 this_sequence A131405 A042243 A041887
Adjacent sequences: A097439 A097440 A097441 this_sequence A097443 A097444 A097445
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KEYWORD
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nonn
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AUTHOR
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Cino Hilliard (hillcino368(AT)gmail.com), Aug 22 2004
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