A174917 Lesser of twin primes p1 such that p2+(p2^2-p1^2) is a prime number.

5, 11, 29, 41, 107, 137, 149, 197, 239, 347, 431, 461, 569, 599, 659, 809, 821, 1019, 1229, 1289, 1481, 1619, 1787, 1877, 1931, 2027, 2129, 2141, 2309, 2339, 2657, 2687, 2801, 2969, 3119, 3329, 3467, 3557, 3581, 4001, 4019, 4127, 4241, 4421, 4547, 4649

Offset

1,1

Comments

5+(7^2-5^2)=5+24=29,...

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Mathematica

lst={}; Do[p1=Prime[n]; p2=p1+2; If[PrimeQ[p2]&&PrimeQ[p2+(p2^2-p1^2)], AppendTo[lst, p1]], {n, 4*6!}]; lst
Select[Partition[Prime[Range[700]], 2, 1], #[[2]]-#[[1]]==2&& PrimeQ[ #[[2]]+ #[[2]]^2-#[[1]]^2]&][[All, 1]] (* Harvey P. Dale, Dec 18 2021 *)

Crossrefs

Cf. A001359, A174913, A174915, A174916

Sequence in context: A144311 A074367 A088486 * A214451 A340544 A062772

Adjacent sequences: A174914 A174915 A174916 * A174918 A174919 A174920

Keyword

nonn

Author

Vladimir Joseph Stephan Orlovsky, Apr 02 2010

Status

approved