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A155176 Perimeter s/6 (divided by 6) 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. 6
2, 5, 40, 77, 287, 590, 1335, 1717, 2882, 3337, 3927, 4030, 6902, 7315, 7740, 8932, 15965, 20592, 26070, 27405, 34277, 34580, 40920, 50692, 92132, 96647, 113575, 139690, 160557, 167167, 220225, 237407, 279720, 300832, 310765, 336777, 389895 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

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

LINKS

Table of n, a(n) for n=1..37.

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, s/6]], {n, 8!}]; lst

CROSSREFS

Cf. A020882, A020886, A020884, A020883, A024364, A024406, A155171, A155173, A155174, A155175

Sequence in context: A109003 A120031 A110066 * A127974 A012801 A183910

Adjacent sequences:  A155173 A155174 A155175 * A155177 A155178 A155179

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, Jan 21 2009

STATUS

approved

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Last modified October 23 17:32 EDT 2019. Contains 328373 sequences. (Running on oeis4.)