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 A100414 #7 Mar 14 2015 15:37:08 %S A100414 21,48034,69926,180461,214591,409473,563715,41630193,253385633342, %T A100414 661494322636 %N A100414 Numbers n such that n is R(n)-th composite number where R(n) is the digit reversal of n (A002808(A004086(n))=n). %C A100414 There is no further term < 3*10^9. %C A100414 a(11) > 3*10^12. [_Donovan Johnson_, Jun 14 2009] %e A100414 41630193 is in the sequence because 41630193 is the 39103614th composite number. %t A100414 Do[s=FromDigits[Reverse[IntegerDigits[n]]];If[s<n&&!PrimeQ[n] &&s==n-PrimePi[n]-1, Print[n]], {n, 2, 42000000}] %Y A100414 Cf. A002808, A004086, A100412, A100413, A100415. %K A100414 base,more,nonn %O A100414 1,1 %A A100414 _Farideh Firoozbakht_, Dec 10 2004 %E A100414 a(9)-a(10) from _Donovan Johnson_, Jun 14 2009