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 A108652 #7 Aug 16 2015 21:41:24 %S A108652 0,1,2,3,4,5,6,7,8,9,10,20,23,24,25,26,27,28,29,30,32,36,37,38,39,40, %T A108652 42,45,46,47,48,49,50,51,54,58,59,60,62,64,67,68,69,70,71,73,76,80,83, %U A108652 84,86,89,90,91,92,93,94,95,98,114,116,117,118,119,124,127,128,129,130,131 %N A108652 Self-erasure surviving numbers. %C A108652 The sequence is finite. %C A108652 There are some n such that n appears between two erased digits, but all such occurrences of n later have one of their digits erased. The first example is 71. Such numbers are included in this version. If they are excluded we get A140665. - _David Wasserman_, May 20 2008 %C A108652 The sequence is finite because there can be no more than ten digits between consecutive erasures. The largest member is 9999986420. - _David Wasserman_, May 20 2008 %e A108652 Take an integer like 36, for example. Concatenate an infinite number of copies of itself: 363636363636363636363636... Put your left index on the first digit (3), jump 3 digits (to the right) with your right index and erase the digit you're landing on (3). Move your left finger (to the right) on the next visible digit (6). Jump thus 6 digits (to the right) with your right finger and erase the digit you're landing on, etc. If the number you started with (36) appears suddenly between two erased digits, you have a "Self-erasure surviving number". %e A108652 In the example below, the erased digits are between parentheses: %e A108652 3636(3)63(6)3(6)36(3)(6)3(6)3636363636... %Y A108652 Cf. A140665. %K A108652 base,easy,fini,nonn %O A108652 0,3 %A A108652 _Eric Angelini_ and _Alexandre Wajnberg_, Jul 06 2005 %E A108652 More terms from _David Wasserman_, May 20 2008