OFFSET
1,1
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..1000
MATHEMATICA
s=0; lst={}; Do[s+=n; p=IntegerPart[s]; If[PrimeQ[p], AppendTo[lst, p]], {n, 0, 7!, Pi}]; lst
Select[Floor[Accumulate[Range[800]]*Pi], PrimeQ] (* Harvey P. Dale, Nov 20 2018 *)
PROG
(PARI) for(n=1, 500, m=floor(n*(n+1)*Pi/2); if(isprime(m), print1(m, ", "))) \\ G. C. Greubel, Jul 28 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
Vladimir Joseph Stephan Orlovsky, Jul 31 2009
EXTENSIONS
Definition clarified by R. J. Mathar, Sep 24 2011
STATUS
approved