A230016 Indices of primes in the tribonacci-like sequence, A214825.

1, 2, 3, 4, 5, 6, 7, 10, 16, 17, 26, 32, 104, 109, 120, 133, 312, 546, 608, 2274, 2527, 2932, 4462, 4680, 6001, 7103, 17402, 17874, 20664, 26341, 27954, 32869, 36204, 41521, 49065, 64172, 66318, 196078

Offset: 1

Author

Robert Price, Feb 22 2014

Keywords

• nonn

Comments

a(39) > 2*10^5.

Links

• Tony D. Noe and Jonathan Vos Post, Primes in Fibonacci n-step and Lucas n-step Sequences, J. of Integer Sequences, Vol. 8 (2005), Article 05.4.4

Crossrefs

Cf. A001590, A100683, A231574, A231575, A232542, A214899, A230607, A020992, A232498, A214727, A081172, A214752, A141523,A214825, A235862.

Programs

Mathematica

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