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 A113492 #14 Mar 13 2017 04:30:36
%S A113492 1,7,11,3,3,4,3,5,11,4,1,2,1,1,4,8,8,2,2,6,6,7,7,3,1,3,4,2,7,2,2,3,2,
%T A113492 2,4,1,3,12,5,2,2,1,3,5,3,4,4,4,14,2,1,2,11,4,6,2,1,2,7,8,4,6,1,3,1,8,
%U A113492 1,2,4,3,12,8,1,2,11,1,2,10,2,3,3,9,1,1
%N A113492 Least integers, starting with 1, so ascending descending base exponent transforms all triprimes.
%C A113492 This is the triprime analogy to A113320.
%H A113492 G. C. Greubel, <a href="/A113492/b113492.txt">Table of n, a(n) for n = 1..1000</a>
%F A113492 a(1) = 1. For n > 1: a(n) = min {n > 0: Sum_{i=1..n} a(i)^a(n-i+1) is a triprime}. a(n) = min {n > 0: Sum_{i=1..n} a(i)^a(n-i+1) in A014612}.
%e A113492 a(1) = 1 by definition.
%e A113492 a(2) = 7 because 1^7 + 7^1 = 8 = 2^3 is a triprime (A014612).
%t A113492 p3[n_] := PrimeOmega[n] == 3; inve[w_] := Total[w^Reverse[w]]; a[1] = 1; a[n_] := a[n] = Block[{k = 0}, While[! p3[ inve@ Append[ Array[a, n - 1], ++k]]]; k]; Array[a, 75] (* _Giovanni Resta_, Jun 13 2016 *)
%Y A113492 Cf. A014612, A113320, A005408, A113122, A113153, A113154, A113336, A113271, A113258, A113257, A113231, A087316, A113208.
%K A113492 easy,nonn
%O A113492 1,2
%A A113492 _Jonathan Vos Post_, Jan 10 2006
%E A113492 Corrected and extended by _Giovanni Resta_, Jun 13 2016