This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A326638 #10 Dec 06 2019 21:45:26 %S A326638 100,1000,101,103,104,135,171,128,119,120,109,121,256,147,239,163,304, %T A326638 370,340,450,240,200,150,250,600,160,130,700,170,131,812,380,168,693, %U A326638 379,300,110,102,106,151,167,107,108,140,111,105,112,114,115,117,118,113,126,129,123,124,125,137,122,149 %N A326638 For any k, the cumulative sum a(1) + a(2) + a(3) + ... + a(k) shares at least three digits with a(k). Lexicographically first sequence of positive integers without duplicate terms having this property. %H A326638 Jean-Marc Falcoz, <a href="/A326638/b326638.txt">Table of n, a(n) for n = 1..10001</a> %e A326638 Here are the first terms of the sequence: %e A326638 100,1000,101,103,104,135,171,128,119,120,... %e A326638 and here are the cumulative sums: %e A326638 100,1100,1201,1304,1408,1543,1714,1842,1961,2081,... %e A326638 If we align a(n) and its cumulative sum, we see that at least three digits are shared: %e A326638 100,1000, 101, 103, 104 ,135, 171, 128, 119, 120,... %e A326638 100,1100,1201,1304,1408,1543,1714,1842,1961,2081,... %Y A326638 Cf. A309151 (where no digit is shared by the cumulative sum), A316914 (where one digit is shared instead of three, by the cumulative sum), A316915 (two digits shared), A326639 (four digits shared), A326640 (five digits shared). %K A326638 base,nonn %O A326638 1,1 %A A326638 _Eric Angelini_ and _Jean-Marc Falcoz_, Jul 15 2019