A242324 Indices of primes in the tribonacci-like sequence A214827.

1, 2, 3, 5, 7, 8, 11, 13, 14, 15, 18, 39, 42, 46, 128, 319, 501, 645, 749, 785, 924, 1786, 1810, 3032, 3053, 3913, 4444, 5611, 6290, 20526, 20850, 23431, 44281, 45981, 103816, 133938

Offset

1,2

Comments

a(37) > 2*10^5.

Links

Table of n, a(n) for n=1..36.

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

Mathematica

a={1, 5, 5}; Print[1]; Print[2]; For[n=3, n<=1000, n++, sum=Plus@@a; If[PrimeQ[sum], Print[n]]; a=RotateLeft[a]; a[[3]]=sum]

Crossrefs

Cf. A001590, A100683, A231574, A231575, A232542, A214899, A230607, A020992, A232498, A214727, A081172, A214752, A141523,A214825, A235862, A214827.

Sequence in context: A189168 A182799 A112929 * A099519 A014121 A287893

Adjacent sequences: A242321 A242322 A242323 * A242325 A242326 A242327

Keyword

nonn,more

Author

Robert Price, May 10 2014

Status

approved