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%I #30 Sep 13 2020 15:14:16
%S 1,2,6,30030,39270,30,42,43890,46410,51870,66,70,510510,78,53130,102,
%T 105,62790,66990,110,10,3,114,67830,71610,72930,130,210,138,154,5,
%U 2310,79170,81510,82110,165,170,9699690,174,182,14,2730,186,84630,190,7,570570,85470,91770,94710,195,98670
%N Lexicographically earliest sequence of positive distinct terms such that the digital root of a(n) is the number of distinct prime factors of a(n+1).
%C All prime numbers are present and appear in their natural order; they follow a term with digital root 1.
%H Carole Dubois, <a href="/A337096/b337096.txt">Table of n, a(n) for n = 1..10000</a>
%e a(1) = 1 with DR (digital root) = 1 and a(2) = 2 has indeed only 1 prime factor;
%e a(2) = 2 with DR = 2 and a(3) = 6 has indeed 2 distinct prime factors (2 and 3);
%e a(3) = 6 with DR = 6 and a(4) = 30030 has indeed 6 distinct prime factors (2,3,5,7,11,13);
%e a(4) = 30030 with DR = 6 and a(5) = 39270 has indeed 6 distinct prime factors (2,3,5,7,11,17);
%e a(5) = 39270 with DR = 3 and a(6) = 30 has indeed 3 distinct prime factors (2,3,5); etc.
%Y Cf. A010888.
%K nonn,base
%O 1,2
%A _Eric Angelini_ and _Carole Dubois_, Aug 15 2020
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