OFFSET
2,1
COMMENTS
Shows the first 204 items; The first appearance in A114233; Sequence is defined for all k>=2.
EXAMPLE
k=2: 2*Prime[3]+Prime[2]=13 is prime, so n(2)=3;
2*Prime[4]+Prime[2]=17
2*Prime[5]+Prime[2]=25, ... 2*Prime[5]+Prime[4]=29 ==> n(4)=5;
MATHEMATICA
Do[n[k] = 0, {k, 2, 2000}]; ct = 0; nm = 0; n2 = 0; n1 = 3; p1 = 5; While[ct < 200, n2 = 1; p2 = Prime[n2]; While[cp = 2*p1 + p2; ! PrimeQ[cp], n2++; p2 = Prime[n2]]; If[n[n2] == 0, n[ n2] = n1; If[n2 > nm, nm = n2]; If[n2 <= 201, ct++ ]; Print[Table[n[k], {k, 2, nm}]]]; n1++; p1 = Prime[n1]];
CROSSREFS
KEYWORD
nonn
AUTHOR
Lei Zhou, Nov 20 2005
STATUS
approved