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A155173
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Short leg A of primitive Pythagorean triangles such that perimeters are Averages of twin prime pairs, q=p+1, a=q^2-p^2, c=q^2+p^2, b=2*p*q, s=a+b+c, s-+1 are primes.
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10
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3, 5, 15, 21, 41, 59, 89, 101, 131, 141, 153, 155, 203, 209, 215, 231, 309, 351, 395, 405, 453, 455, 495, 551, 743, 761, 825, 915, 981, 1001, 1149, 1193, 1295, 1343, 1365, 1421, 1529, 1659, 1853, 2105, 2171, 2205, 2255, 2373, 2409, 2411, 2451, 2513, 2561, 2649
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| p=1,q=2,a=3,b=4,c=5,s=12-+1 primes, ...
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MATHEMATICA
| lst={}; Do[p=n; q=p+1; a=q^2-p^2; c=q^2+p^2; b=2*p*q; s=a+b+c; If[PrimeQ[s-1]&&PrimeQ[s+1], AppendTo[lst, a]], {n, 8!}]; lst
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CROSSREFS
| Cf. A020882, A020886, A020884, A020883, A024364, A024406, A155171
Sequence in context: A101129 A177916 A128396 * A202505 A121219 A113732
Adjacent sequences: A155170 A155171 A155172 * A155174 A155175 A155176
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KEYWORD
| nonn
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AUTHOR
| Vladimir Orlovsky (4vladimir(AT)gmail.com), Jan 21 2009
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