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A174916
Lesser of twin primes p1 such that p1 + p2^2 - p1^2 is a prime number.
6
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
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
KEYWORD
nonn
AUTHOR
STATUS
approved