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A299101
Indices of (probable) primes in A030221.
15
2, 3, 5, 6, 8, 9, 15, 18, 23, 53, 114, 194, 564, 575, 585, 2594, 3143, 4578, 4970, 9261, 11508, 13298, 30018, 54993, 198476
OFFSET
1,1
COMMENTS
From a problem in A269254. For detailed theory, see [Hone].
a(25) > 2*10^5. - Robert Price, Jul 03 2020
LINKS
Andrew N. W. Hone, et al., On a family of sequences related to Chebyshev polynomials, arXiv:1802.01793 [math.NT], 2018.
FORMULA
A299109(n) = A030221(a(n)). - R. J. Mathar, Jul 22 2022
MATHEMATICA
-1 + Position[Nest[Append[#, 5 #[[-1]] - #[[-2]] ] &, {1, 6}, 2600], _?PrimeQ][[All, 1]] (* Michael De Vlieger, Jul 03 2020 *)
KEYWORD
nonn,hard,more
AUTHOR
EXTENSIONS
a(24) from Robert Price, Jul 03 2020
STATUS
approved