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A155174
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Long leg B 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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8
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4, 12, 112, 220, 840, 1740, 3960, 5100, 8580, 9940, 11704, 12012, 20604, 21840, 23112, 26680, 47740, 61600, 78012, 82012, 102604, 103512, 122512, 151800, 276024, 289560, 340312, 418612, 481180, 501000, 660100, 711624, 838512, 901824, 931612
(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, b]], {n, 8!}]; lst
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CROSSREFS
| Cf. A020882, A020886, A020884, A020883, A024364, A024406, A155171, A155173
Sequence in context: A070040 A079822 A080448 * A053491 A032323 A053551
Adjacent sequences: A155171 A155172 A155173 * A155175 A155176 A155177
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KEYWORD
| nonn
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AUTHOR
| Vladimir Orlovsky (4vladimir(AT)gmail.com), Jan 21 2009
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