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%I #9 Oct 17 2021 15:26:18
%S 1,1,1,2,2,1,3,3,2,4,4,1,5,5,3,6,6,2,7,7,4,8,8,1,9,9,5,10,10,3,11,11,
%T 6,12,12,2,13,13,7,14,14,4,15,15,8,16,16,1,17,17,9,18,18,5,19,19,10,
%U 20,20,3,21,21,11,22,22,6,23,23,12,24,24,2,25,25,13
%N Lexicographically earliest sequence of positive integers such that for any n > 0, the sum of the indices k < n such that a(k) = a(n) is less than or equal to n.
%C Every integer appears infinitely many times.
%C See table A348357 where the integers are arranged according to the present sequence.
%F a(n) = 1 iff n belongs to A098011.
%o (PARI) s=vector(25); for (n=1, 75, for (k=1, oo, if (s[k]<=n, print1 (k", "); s[k]+=n; break)))
%Y Cf. A098011, A348330, A348356, A348357.
%K nonn
%O 1,4
%A _Rémy Sigrist_, Oct 13 2021