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 A090315 #9 Jul 10 2017 10:47:51 %S A090315 1,2,4,6,14641,44,0,24,484,272,0,294,0,291008,44944,264,0,252,0,2992, %T A090315 0,2532352,0,2508,10004000600040001,2977792,1002001,2112,0,63536,0, %U A090315 4224,0,44356665344,0,2772,0,2380651036672,0,42224,0,6336,0,2937856,698896,0 %N A090315 Least k such that k and digit reversal of k both have n divisors, or 0 if no such number exists. %C A090315 For a(7) one needs a number of the form p^6 whose digit reversal is q^6, p, q are primes. Hence a(7) perhaps is zero (not sure). Conjecture: There are infinitely many nonzero terms as well as zeros in this sequence. %C A090315 Zeros are unproved. I have checked for a(21) up to 10^13, a(46) up to 10^14, a(33) up to 10^18, a(39) up to 10^20, a(35) up to 10^30 and the rest (7, 11, 13, 17, 19, 23, 29, 31, 37, 41 and 43) up to at least 10^48. - _David Wasserman_, Nov 01 2005 %e A090315 a(8) =24, tau(24) = tau(42) = 8. %Y A090315 Cf. A083753. %K A090315 base,nonn %O A090315 1,2 %A A090315 _Amarnath Murthy_, Dec 01 2003 %E A090315 More terms from _David Wasserman_, Nov 01 2005