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A155187 Prime numbers q of primitive Pythagorean triangles such that perimeters are Averages of twin prime pairs, p+1=q(prime), a=q^2-p^2, c=q^2+p^2, b=2*p*q, ar=a*b/2; s=a+b+c, s-+1 are primes. +0
1
2, 3, 11, 71, 227, 491, 683, 1103, 1187, 2591, 3923, 4271, 4931, 6737, 7193, 7703, 8093, 8753, 8963, 9173, 9377, 10271, 13043, 13451, 13997, 15233, 15443, 15803, 15887, 17957, 18701, 19961, 20681, 21701, 22031, 22073, 24371, 24473, 24683 (list; graph; listen)
OFFSET

1,1

COMMENT

p=1,q=2(prime),a=3,b=4,c=5,s=12-+1 primes, ...

MATHEMATICA

lst={}; Do[p=n; q=p+1; a=q^2-p^2; c=q^2+p^2; b=2*p*q; ar=a*b/2; s=a+b+c; If[PrimeQ[s-1]&&PrimeQ[s+1], If[PrimeQ[q], AppendTo[lst, q]]], {n, 8!}]; lst

CROSSREFS

Cf. A020882, A020886, A020884, A020883, A024364, A024406, A155171, A155173, A155174, A155175, A155176, A155177, A155178, A155180, A088483, A001844, A096891, A066885, A099776, A110494, A081589, A155185, A019389, A062090, A050150, A155186, A068231, A129517, A054574, A132281

Sequence in context: A066046 A065597 A001052 this_sequence A109132 A008510 A042165

Adjacent sequences: A155184 A155185 A155186 this_sequence A155188 A155189 A155190

KEYWORD

nonn

AUTHOR

Vladimir Orlovsky (4vladimir(AT)gmail.com), Jan 21 2009

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Last modified December 19 12:50 EST 2009. Contains 171053 sequences.


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