A248700 Indices of primes in the Heptanacci numbers sequence A122189.

8, 14, 22, 102495, 130447, 173590

Offset

1,1

Comments

a(7) > 2*10^5.

Links

Table of n, a(n) for n=1..6.

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={0, 0, 0, 0, 0, 0, 1}; For[n=7, n<=1000, n++, sum=Plus@@a; If[PrimeQ[sum], Print[n]]; a=RotateLeft[a]; a[[7]]=sum]

Crossrefs

Cf. A001590, A001631, A100683, A231574, A231575, A232542, A214899, A230607, A020992, A232498, A214727, A081172, A214752, A141523, A214825, A235862, A000288, A000322, A122189.

Sequence in context: A238290 A100315 A224952 * A001049 A134445 A100508

Adjacent sequences: A248697 A248698 A248699 * A248701 A248702 A248703

Keyword

nonn,more

Author

Robert Price, Dec 02 2014

Status

approved