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A155171
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Numbers p 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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1, 2, 7, 10, 20, 29, 44, 50, 65, 70, 76, 77, 101, 104, 107, 115, 154, 175, 197, 202, 226, 227, 247, 275, 371, 380, 412, 457, 490, 500, 574, 596, 647, 671, 682, 710, 764, 829, 926, 1052, 1085, 1102, 1127, 1186, 1204, 1205, 1225, 1256, 1280, 1324, 1325, 1331
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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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, n]], {n, 8!}]; lst
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CROSSREFS
| Cf. A020882, A020886, A020884, A020883, A024364, A024406
Sequence in context: A105770 A152211 A125852 * A049830 A022302 A023855
Adjacent sequences: A155168 A155169 A155170 * A155172 A155173 A155174
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KEYWORD
| nonn
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AUTHOR
| Vladimir Orlovsky (4vladimir(AT)gmail.com), Jan 21 2009
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