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 A339673 #69 Apr 01 2021 21:25:58 %S A339673 25427,31427,32027,32087,32093,37032,37583,37643,37693,49390,49501, %T A339673 50611,60490,60501,60611,61600,61601,61611,61711,61721,61722,62958, %U A339673 62959,62969,63069,64069,65427,72958,72959,72969,73069,73958,73959,73969,74058,74059,74068 %N A339673 Numbers that cannot be expressed as sum of at most nine repdigits numbers. One may not add two integers with the same repeated digit. %C A339673 Computer solutions found by Oscar Volpatti. %H A339673 Chai Wah Wu, <a href="/A339673/b339673.txt">Table of n, a(n) for n = 1..10000</a> %H A339673 Carlos Rivera and Rodolfo Kurchan, <a href="http://www.primepuzzles.net/puzzles/puzz_1027.htm">Puzzle 1027. Integers as sum of distinct repdigits</a>, The prime puzzles & problems connection. %e A339673 8888 and 888 cannot be used in the same expression. %e A339673 Examples: 25599 = 22222 + 3333 + 44, 98765 = 88888 + 7777 + 1111 + 555 + 333 + 99 + 2. %e A339673 It appears that 987654 and 987650 cannot be expressed in this way. %e A339673 25427 is the smallest number without solution. %e A339673 Smallest solution that ends with digits from 0 to 9 (solutions from Oscar Volpatti): 0: 49390 1: 49501 2: 37032 3: 32093 4: 143204 5: 254315 6: 74106 7: 25427 8: 62958 9: 62959. %Y A339673 Cf. A235400. %K A339673 base,nonn %O A339673 1,1 %A A339673 _Rodolfo Kurchan_, Jan 17 2021