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A048270
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Sequence of 2 Pythagorean triangles, each with a leg and hypotenuse prime. The leg of the second triangle is the hypotenuse of the first.
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3
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3, 11, 19, 59, 271, 349, 521, 929, 1031, 1051, 1171, 2381, 2671, 2711, 2719, 3001, 3499, 3691, 4349, 4691, 4801, 4999
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| Subsequence of A048161. - Lekraj Beedassy (blekraj(AT)yahoo.com), Sep 16 2005
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LINKS
| H. Dubner and T. Forbes, Prime Pythagorean triangles, J. Integer Seqs., Vol. 4 (2001), #01.2.3.
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FORMULA
| For each p(n), there is a q=(p*p+1)/2 and r=(q*q+1)/2 such that p, q, r, are all prime
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EXAMPLE
| P(1)=3 because 3 is prime, 5=(3*3+1)/2 and 13=(5*5+1)/2, 5,13 both prime
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CROSSREFS
| A048161.
Sequence in context: A007520 A163851 A116945 * A183459 A176872 A088733
Adjacent sequences: A048267 A048268 A048269 * A048271 A048272 A048273
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KEYWORD
| nonn
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AUTHOR
| Harvey Dubner (harvey(AT)dubner.com)
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EXTENSIONS
| It is conjectured that there is an infinite number of such pairs of triangles.
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