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%I #16 Jul 31 2024 11:08:20
%S 2,3,4,7,8,9,10,12,20,30,33,66,76,77,82,87,98,180,205,360,553,719,766,
%T 1390,1879,1999,4033,5620,16506,17436,23676,24428,27758,31932,58199,
%U 67661,85040,102023,185595
%N Indices of primes in A001644 (the Lucas 3-step numbers).
%C The sequence of generalized tribonacci numbers is defined as beginning with 1, 3, 7. Subsequent terms are the sum of the previous three terms. Note that the sequence of these generalized tribonacci numbers has many more primes than the tribonacci sequence A000073 (whose prime indices are in A092835).
%C a(40) > 2*10^5. - _Robert Price_, Dec 24 2013
%H Tony D. Noe and Jonathan Vos Post, <a href="http://www.cs.uwaterloo.ca/journals/JIS/VOL8/Noe/noe5.html">Primes in Fibonacci n-step and Lucas n-step Sequences,</a> J. of Integer Sequences, Vol. 8 (2005), Article 05.4.4
%F A001644(a(n)) = A105762(n). - _Arthur O'Dwyer_, Jul 26 2024
%Y Cf. A104577 (indices of prime generalized tetranacci numbers).
%Y Cf. A000073, A001644, A092835, A105762.
%K nonn,more
%O 1,1
%A _T. D. Noe_, Mar 16 2005
%E a(37)-a(39) from _Robert Price_, Dec 24 2013
%E Name clarified by _Arthur O'Dwyer_, Jul 25 2024