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%I #8 Dec 31 2023 00:22:03
%S 1,3,6,9,12,23,10,5,51,39,18,17,27,43,61,26,67,11,8,83,69,16,7,88,4,
%T 65,93,22,243,128,49,38,24,121,80,75,138,79,217,102,135,50,32,91,81,
%U 48,230,28,66,225,77,158,151,178,34,125,420,97,468,62,56,475,13,170,211,94,299,311,604,45
%N Lexicographically earliest sequence of distinct positive integers such that n divides the sum of the distinct prime factors (sopf) of a(n - 1) + a(n), with a(1) = 1.
%H Éric Angelini, <a href="https://cinquantesignes.blogspot.com/2023/12/palindromes-with-distinct-prime-factors.html">Sums of distinct prime factors</a>, Personal blog, December 2023.
%e a(1) + a(2) = 4, sopf(4) = 2 and n=2 divides 2.
%e a(6) + a(7) = 33, sopf(33) = 14 and n=7 divides 14.
%t a[1]=1;a[n_]:=a[n]=(k=1;While[MemberQ[Array[a,n-1],k]|| Mod[Total[First/@FactorInteger[k+a[n-1]]],n]!=0,k++];k);Array[a,70]
%Y Cf. A008472.
%K nonn
%O 1,2
%A _Giorgos Kalogeropoulos_ and _Eric Angelini_, Dec 05 2023
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