cp's OEIS Frontend

A357432 a(1) = 1; a(2) = 2; for n > 2, a(n) is the smallest positive number not occurring earlier such that a(n) plus the sum of all previous terms appears in the string concatenation of a(1)..a(n-1).

%I A357432 #13 Jan 16 2023 09:10:46
%S A357432 1,2,9,17,62,38,47,115,93,87,122,30,88,51,85,4,3,31,32,21,221,64,68,
%T A357432 302,53,116,92,268,42,48,18,78,76,97,50,153,233,108,63,20,8,16,89,12,
%U A357432 77,537,24,377,83,46,306,28,107,197,170,126,61,566,218,82,43,25,14,148,147,6,209,145,37,103
%N A357432 a(1) = 1; a(2) = 2; for n > 2, a(n) is the smallest positive number not occurring earlier such that a(n) plus the sum of all previous terms appears in the string concatenation of a(1)..a(n-1).
%C A357432 The sequence is conjectured to be a permutation of the positive integers. In the first 20000 terms the fixed points are 393, 514, 1546, and 7854, although more likely exist.
%H A357432 Scott R. Shannon, <a href="/A357432/a357432.png">Image of the first 20000 terms</a>. The green line is a(n) = n.
%e A357432 a(4) = 17 as a(1) + a(2) + a(3) + 17 = 1 + 2 + 9 + 17 = 29, and "29" appears in the string concatenation of a(1)..a(3) = "129".
%Y A357432 Cf. A357433 (base 2), A000027, A007908, A000217, A351753, A337227.
%K A357432 nonn,base
%O A357432 1,2
%A A357432 _Scott R. Shannon_, Sep 28 2022