OFFSET
1,2
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..10000
MATHEMATICA
a[n_]:=Floor[(n-1/2)*(2+2^(1/2))+1/2];
Table[a[n], {n, 1, 120}] (* A063957 *)
t1={}; Do[If[PrimeQ[a[n]], AppendTo[t1, a[n]]], {n, 1, 600}]; t1
t2={}; Do[If[PrimeQ[a[n]], AppendTo[t2, n]], {n, 1, 600}]; t2
t3={}; Do[If[MemberQ[t1, Prime[n]], AppendTo[t3, n]], {n, 1, 400}]; t3
PROG
(PARI) isok(k) = isprime(floor((k-1/2)*(2+sqrt(2))+1/2)); \\ Michel Marcus, Jan 30 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
Clark Kimberling, Jan 23 2011
STATUS
approved