A139778 Lesser of twin primes p1 such that p1^3 + p2^2 are average of twin primes. p1 and p2 twin primes, p1 < p2.

3371, 4091, 5231, 18521, 42179, 45119, 48821, 49121, 71711, 72101, 75539, 83639, 91571, 94151, 94559, 115979, 117191, 128111, 128339, 157769, 179819, 186299, 189491, 203321, 208889, 213359, 233159, 248201, 250049, 251969, 259451, 267299, 273899, 275159

Offset

1,1

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Mathematica

a={}; Do[p1=Prime[n]; p2=Prime[n+1]; pp=p1^3+p2^2; If[(p2-p1)==2&&PrimeQ[pp-1]&&PrimeQ[pp+1], AppendTo[a, p1]], {n, 10^4}]; Print[a];
atpQ[{p1_, p2_}]:=Module[{c=p1^3+p2^2}, And@@PrimeQ[{c-1, c+1}]]; Transpose[ Select[ Select[Partition[Prime[Range[100000]], 2, 1], Last[#] - First[#] == 2&], atpQ]][[1]] (* Harvey P. Dale, Jul 13 2012 *)

Prog

(Magma) [p: p in PrimesUpTo(280000)| IsPrime(p+2) and IsPrime(a-1) and IsPrime(a+1) where a is p^3+(p+2)^2]; // Marius A. Burtea, Dec 31 2019

Crossrefs

Cf. A001359, A006512, A001097.

Sequence in context: A293651 A212948 A204471 * A346025 A178506 A248443

Adjacent sequences: A139775 A139776 A139777 * A139779 A139780 A139781

Keyword

nonn

Author

Vladimir Joseph Stephan Orlovsky, May 16 2008

Extensions

More terms from Harvey P. Dale, Jul 13 2012

Status

approved