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%I #10 Jul 27 2020 01:30:14
%S 1,2,5,6,11,14,21,23,26,27,29,30,47,62,85,86,87,90,95,106,107,111,117,
%T 122,125,126,171,174,183,186,187,191,219,234,237,238,239,246,251,254,
%U 341,347,349,351,363,383,426,431,442,447,470,471,474,479,491,495,501
%N a(1) = 1; a(2) = 2; for n > 2, a(n) is the least number > a(n-1) whose binary representation is uniquely the concatenation of the binary representations of two distinct earlier terms.
%C This sequence is inspired by Ulam sequence (A002858).
%H Rémy Sigrist, <a href="/A336527/b336527.txt">Table of n, a(n) for n = 1..10000</a>
%H Rémy Sigrist, <a href="/A336527/a336527.gp.txt">PARI program for A336527</a>
%e The first terms, alongside the binary representations of the natural numbers with the corresponding concatenations of distinct smaller terms, are:
%e n a(n) k bin(k) concatenations
%e - ---- -- ------ --------------
%e 1 1 1 1
%e 2 2 2 10
%e 3 11
%e 4 100
%e 3 5 5 101 10|1
%e 4 6 6 110 1|10
%e 7 111
%e 8 1000
%e 9 1001
%e 10 1010
%e 5 11 11 1011 101|1
%e 12 1100
%e 13 1101 1|101, 110|1
%e 6 14 14 1110 1|110
%o (PARI) See Links section.
%Y Cf. A002858, A336528 (decimal variant).
%K nonn,base
%O 1,2
%A _Rémy Sigrist_, Jul 24 2020
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