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A235396
Indices of primes in the tribonacci-like sequence, A081172.
0
3, 4, 5, 9, 12, 16, 24, 32, 101, 116, 245, 34553, 52517, 99245, 140197
OFFSET
1,1
COMMENTS
a(16) > 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
MATHEMATICA
a={1, 1, 0}; For[n=3, n<=1000, n++, sum=Plus@@a; If[PrimeQ[sum], Print[n]]; a=RotateLeft[a]; a[[3]]=sum]
KEYWORD
nonn
AUTHOR
Robert Price, Jan 09 2014
STATUS
approved