# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a336527 Showing 1-1 of 1 %I A336527 #10 Jul 27 2020 01:30:14 %S A336527 1,2,5,6,11,14,21,23,26,27,29,30,47,62,85,86,87,90,95,106,107,111,117, %T A336527 122,125,126,171,174,183,186,187,191,219,234,237,238,239,246,251,254, %U A336527 341,347,349,351,363,383,426,431,442,447,470,471,474,479,491,495,501 %N A336527 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 A336527 This sequence is inspired by Ulam sequence (A002858). %H A336527 Rémy Sigrist, Table of n, a(n) for n = 1..10000 %H A336527 Rémy Sigrist, PARI program for A336527 %e A336527 The first terms, alongside the binary representations of the natural numbers with the corresponding concatenations of distinct smaller terms, are: %e A336527 n a(n) k bin(k) concatenations %e A336527 - ---- -- ------ -------------- %e A336527 1 1 1 1 %e A336527 2 2 2 10 %e A336527 3 11 %e A336527 4 100 %e A336527 3 5 5 101 10|1 %e A336527 4 6 6 110 1|10 %e A336527 7 111 %e A336527 8 1000 %e A336527 9 1001 %e A336527 10 1010 %e A336527 5 11 11 1011 101|1 %e A336527 12 1100 %e A336527 13 1101 1|101, 110|1 %e A336527 6 14 14 1110 1|110 %o A336527 (PARI) See Links section. %Y A336527 Cf. A002858, A336528 (decimal variant). %K A336527 nonn,base %O A336527 1,2 %A A336527 _Rémy Sigrist_, Jul 24 2020 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE