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 A050741 #20 Oct 16 2019 01:33:02 %S A050741 0,1,2,3,4,5,6,7,8,9,11,13,14,16,17,18,19,22,23,24,25,26,27,28,29,31, %T A050741 32,33,36,37,39,41,42,43,44,45,48,49,51,52,53,54,55,56,57,59,61,63,64, %U A050741 66,68,69,71,72,73,74,75,77,78,79,81,82,84,86,87,89,91,92,93,95,96,97 %N A050741 Numbers k such that the decimal expansion of k^2 contains no pair of consecutive equal digits. %H A050741 Zak Seidov and Michael De Vlieger, <a href="/A050741/b050741.txt">Table of n, a(n) for n = 1..10471</a>, a(n) < 25,000 (First 1057 terms from Zak Seidov) %e A050741 10 is absent because 10^2=100 with repeating 0, %e A050741 12 is absent because 12^2=144 with repeating 4, %e A050741 21 is absent because 21^2=441 with repeating 4. %t A050741 Select[Range[0,97],FreeQ[Differences[IntegerDigits[#^2]],0]&] (* _Jayanta Basu_, May 31 2013 *) %Y A050741 Cf. A043096, A050749, A135463, A134962. %K A050741 nonn,base %O A050741 1,3 %A A050741 _Patrick De Geest_, Sep 15 1999 %E A050741 Edited by _N. J. A. Sloane_, Mar 16 2008