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A159071
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Primes which are the sum of 6 consecutive triangular numbers A000217.
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1
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83, 251, 683, 1091, 2531, 5051, 7211, 11171, 15131, 16883, 18731, 21683, 24851, 29411, 33083, 42491, 59651, 85691, 107171, 109451, 114083, 133571, 138683, 151883, 160091, 189011, 201251, 204371, 236891, 268211, 271811, 297683, 309131
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OFFSET
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1,1
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COMMENTS
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Primes of the form 3*k^2 + 18*k + 35 = 3*(k+3)^2 + 8, k >= 0. [R. J. Mathar, Apr 06 2009]
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LINKS
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EXAMPLE
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MATHEMATICA
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tr[a_]:=Module[{x}, s=0; If[a<0, b=Abs[a]+1, b=a]; For[i=1, i<b, s+=i; i++ ]; x=s]; lst={}; Do[a1=tr[n]; b1=tr[n+1]; c1=tr[n+2]; d1=tr[n+3]; e1=tr[n+4]; f1=tr[n+5]; p=a1+b1+c1+d1+e1+f1; If[PrimeQ[p], AppendTo[lst, p]], {n, -2, 6!}]; lst
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PROG
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(Magma) [a: n in [2..400] | IsPrime(a) where a is 3*n^2+8]; // Vincenzo Librandi, Dec 02 2011
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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