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 A158699 #8 Nov 30 2014 11:45:20 %S A158699 0,1,2,3,4,5,6,7,8,9,10,21,32,43,54,65,76,87,98,109,210,321,432,543, %T A158699 654,765,876,987,1098,2109,3210,4321,5432,6543,7654,8765,9876,10987, %U A158699 21098,32109,43210,54321,65432,76543,87654,98765,109876,210987,321098,432109,543210 %N A158699 Start with 0; then add one to each single digit. %C A158699 If 9 occurs anywhere except at the start of the number it is replaced by 0, but an initial 9 is replaced by 10. - _N. J. A. Sloane_, Mar 27 2009 %e A158699 6543 -> 7654 %e A158699 2109 -> 3210 %e A158699 98765 -> 109876, etc. %Y A158699 Cf. A061511. %K A158699 nonn,base %O A158699 0,3 %A A158699 _Ruben Gil_, Mar 26 2009