

A063714


Values of r occurring in A063713.


2



3, 3, 5, 3, 3, 5, 3, 19, 5, 3, 7, 29, 3, 5, 3, 5, 3, 43, 5, 3, 7, 3, 7, 3, 5, 3, 11, 3, 5, 5, 3, 7, 89, 7, 3, 5, 3, 3, 5, 3, 13, 113, 7, 13, 127, 5, 3, 11, 137, 139, 5, 13, 3, 7, 3, 5, 5, 3, 7, 3, 13, 5, 19, 3, 3, 31, 197, 199, 7, 13, 17, 11, 3, 5, 3, 229, 5, 3, 11, 5, 11, 3, 19, 3, 7, 3, 7
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OFFSET

1,1


COMMENTS

This is not a mere union of A002373 and A020483 because of the minimality property of these sequences.


LINKS

Robert Israel, Table of n, a(n) for n = 1..10000


MAPLE

f:= proc(n) local k;
k:= 2;
while k < 2*n do
k:= nextprime(k);
if isprime(2*n+k) and isprime(2*nk) then return k fi
od;
NULL
end proc:
map(f, [$1..400]); # Robert Israel, Oct 09 2017


MATHEMATICA

f[n_] := {AnyTrue[Prime[Range[PrimePi[2n2]]], (r = #; PrimeQ[2n+r] && PrimeQ[2nr])&], r}; Select[f /@ Range[200], #[[1]] =!= False &][[All, 2]] (* JeanFrançois Alcover, Feb 14 2018 *)


CROSSREFS

Cf. A063713, A002373, A020483.
Sequence in context: A202106 A136019 A242017 * A235649 A113965 A162277
Adjacent sequences: A063711 A063712 A063713 * A063715 A063716 A063717


KEYWORD

nonn,look


AUTHOR

Reinhard Zumkeller, Aug 10 2001


STATUS

approved



