A174916 Lesser of twin primes p1 such that p1 + p2^2 - p1^2 is a prime number.

3, 5, 11, 17, 29, 71, 101, 281, 311, 419, 461, 521, 599, 617, 641, 659, 809, 827, 857, 881, 1019, 1061, 1277, 1289, 1319, 1607, 1721, 1949, 2027, 2111, 2141, 2309, 2339, 2381, 2591, 2729, 2801, 3329, 3557, 3581, 3767, 3851, 4049, 4127, 4157, 4217, 4229

Offset

1,1

Comments

3+(5^2-3^2)=3+16=19,..

Let x be the lesser of twin prime pairs. The sequence contains terms such that 5*x+4 is prime. - Harvey P. Dale, Sep 11 2012

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[p1+(p2^2-p1^2)], AppendTo[lst, p1]], {n, 1000}]; lst
With[{ltp=Transpose[Select[Partition[Prime[Range[600]], 2, 1], #[[2]]- #[[1]]==2&]][[1]]}, Select[ltp, PrimeQ[5#+4]&]] (* Harvey P. Dale, Sep 11 2012 *)

Crossrefs

Cf. A001359, A174913, A174915.

Sequence in context: A090795 A087732 A278053 * A309433 A309436 A309437

Adjacent sequences: A174913 A174914 A174915 * A174917 A174918 A174919

Keyword

nonn

Author

Vladimir Joseph Stephan Orlovsky, Apr 02 2010

Status

approved