A233190 Indices of primes in the tribonacci-like sequence, A214899.

0, 2, 3, 9, 13, 27, 35, 39, 87, 95, 97, 99, 113, 131, 233, 971, 3851, 5637, 6553, 106099

Offset: 1

Author

Robert Price, Dec 05 2013

Keywords

• nonn

Comments

a(21) > 2*10^5.

Crossrefs

Cf. A001590, A100683, A231574, A231575, A232542, A214899, A230607.

Programs

Mathematica

a={2,1,2};Print[1],Print[2];For[n=3,n<=1000,n++,sum=Plus@@a;If[PrimeQ[sum],Print[n]];a=RotateLeft[a]; a[[3]]=sum]