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 A087988 #13 Oct 25 2015 17:33:31 %S A087988 0,1,2,11,101,111,1001,10001,10101,11011,100001,101101,110011,1000001, %T A087988 1001001,1100011,10000001,10011001,10100101,11000011,100000001, %U A087988 100010001,100101001,101000101,110000011,1000000001,1000110001 %N A087988 Palindromic numbers whose squares and cubes are equally palindromic. %C A087988 Numbers n such that n, n^2 and n^3 are all palindromes. %C A087988 Essentially A002780 with two terms removed, 7 and 2201. %e A087988 11^2=121, 11^3=1331. %p A087988 rev:=proc(a) local aa,ct: aa:=convert(a,base,10): ct:=nops(aa): add(10^(ct-j)*aa[j],j=1..ct) end: p:=proc(n) if rev(n)=n and rev(n^2)=n^2 and rev(n^3)=n^3 then n else fi end: seq(p(n),n=0..12*10^5); # _Emeric Deutsch_, May 01 2005 %o A087988 (PARI) ispal(n) = my(d = digits(n)); Vecrev(d) == d; %o A087988 isok(n) = ispal(n) && ispal(n^2) && ispal(n^3); \\ _Michel Marcus_, Oct 25 2015 %Y A087988 Cf. A002779, A002781. %Y A087988 Intersection of A002113, A002778 and A002780. %K A087988 nonn,base %O A087988 1,3 %A A087988 _Labos Elemer_, Oct 01 2003 %E A087988 More terms from _Ray Chandler_, Oct 05 2003 %E A087988 Edited by _N. J. A. Sloane_, Aug 29 2008 at the suggestion of _R. J. Mathar_