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A165261
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Long legs of primitive Pythagorean triples which have a perimeter which is the average of a twin prime pair.
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2
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4, 12, 77, 112, 143, 195, 209, 220, 299, 420, 425, 520, 527, 629, 700, 840, 868, 988, 1023, 1085, 1127, 1209, 1305, 1421, 1480, 1720, 1740, 1900, 2001, 2021, 2255, 2296, 2320, 2331, 2332, 2499, 2520, 2548, 2583, 2604, 2752, 2829, 2964, 3021, 3256, 3311
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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EXAMPLE
| see A165250.
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MATHEMATICA
| amax=10^5; lst={}; k=0; q=12!; Do[If[(e=((n+1)^2-n^2))>amax, Break[]]; Do[If[GCD[m, n]==1, a=m^2-n^2; b=2*m*n; If[GCD[a, b]==1, If[a>b, {a, b}={b, a}]; If[a>amax, Break[]]; c=m^2+n^2; x=a+b+c; If[PrimeQ[x-1]&&PrimeQ[x+1], k++; AppendTo[lst, b]]]], {m, n+1, 12!, 2}], {n, 1, q, 1}]; Union@lst
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CROSSREFS
| Cf. A020883, A014574, A165260, A165262.
Sequence in context: A190340 A133666 A078628 * A027145 A010370 A197852
Adjacent sequences: A165258 A165259 A165260 * A165262 A165263 A165264
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KEYWORD
| nonn
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AUTHOR
| Vladimir Orlovsky (4vladimir(AT)gmail.com), Sep 11 2009
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