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 A115900 #13 Jul 15 2021 20:39:02 %S A115900 1,2,3,4,5,219,322,375,22248,32065,47827,1406744,2144055,2991368, %T A115900 3626587,4909369,172133971,177457001,328030055,3128669654,8345867631, %U A115900 19649249526,45179367929,47228405729,48534773039,49583585599,2127577449846,2191781701563,3972961263797 %N A115900 Numbers k such that k + sigma(k) and k + phi(k) are palindromes. %C A115900 Intersection of A115895 and A115896. %C A115900 a(27) > 10^11. 3972961263797 is also a term. - _Donovan Johnson_, May 31 2013 %C A115900 a(30) > 10^13. - _Giovanni Resta_, Jun 05 2013 %e A115900 4909369 + sigma(4909369) = 9823289 and 4909369 + phi(4909369) = 9814189. %Y A115900 Cf. A115895, A115896. %K A115900 nonn,base %O A115900 1,2 %A A115900 _Giovanni Resta_, Feb 06 2006 %E A115900 a(17)-a(26) from _Donovan Johnson_, Oct 05 2010 %E A115900 a(27)-a(29) from _Giovanni Resta_, Jun 05 2013