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%I #31 Nov 15 2023 08:05:36
%S 1,2,3,7,23,47,139,283,659,1319,8637,20147,83491,169861,999013,
%T 3797401,8153567,55443959,187814447,646611887
%N Indices of records in A366927.
%C The primes may not be in order. a(3) = 7, but the three primes are 2, 3, and 7.
%t r = 0;
%t s = Array[-1 + CountDistinct@ Rest@ NestWhileList[{#1 - #1/#2, #2} & @@ {First[#], FactorInteger[First[#]][[1, 1]]} &, {#, #}, Last[#] > 1 &][[All, -1]] &, 2^16, 2];
%t {1}~Join~Reap[Do[If[# > r, r = #; Sow[i + 1]] &[s[[i]]], {i, Length[s]}] ][[-1, 1]] (* _Michael De Vlieger_, Nov 08 2023 *)
%Y Cf. A366927.
%K nonn,more
%O 1,2
%A _Robert G. Wilson v_, Oct 31 2023