

A282707


The least prime p of prime triple p,q,r such that q  p = 2n and r  q = 2n + 2.


1



5, 19, 83, 401, 787, 2621, 13367, 7417, 30893, 3947, 51361, 121637, 119363, 99289, 325349, 286301, 317089, 832217, 570743, 38461, 232217, 871349, 539947, 206651, 2827109, 824287, 2592929, 5174063, 2901931
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OFFSET

1,1


COMMENTS

The sequence is not monotonic.


LINKS



EXAMPLE

a(1)=5 because 5, 5 + 2 = 7 and 7 + 4 = 11 are consecutive primes,
a(2)=19 because 19, 19 + 4 = 23 and 23 + 6 = 29 are consecutive primes,
a(3)=83 because 83, 83 + 6 = 89 and 89 + 8 = 97 are consecutive primes.


PROG

(PARI) v=vector(1000); p=2; q=3; forprime(r=5, 1e9, d=qp; if(rq==d+2 && v[d/2]==0, v[d/2]=p; print("a("d/2") = "p)); p=q; q=r) \\ Charles R Greathouse IV, Mar 01 2017


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



