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 A247386 #12 Feb 07 2017 10:27:11
%S A247386 0,0,1,6,30,130,570,2436,10696,47160,213660,981640,4625016,22171656,
%T A247386 108766840,543350640,2772404160,14402353216,76294507536,411229473120,
%U A247386 2257073089120,12595032754080,71481175794336,412117251151936,2413922299708800,14352066564086400
%N A247386 Sum of the major index over all standard Young tableaux with n cells.
%C A247386 Also sum of positions of all ascents in ballot sequences of length n, see example.
%H A247386 Alois P. Heinz, <a href="/A247386/b247386.txt">Table of n, a(n) for n = 0..40</a>
%H A247386 Wikipedia, <a href="https://en.wikipedia.org/wiki/Young_tableau">Young tableau</a>
%F A247386 a(n) = Sum_{k=1..n*(n-1)/2} k*A232439(n,k).
%e A247386 The 10 ballot sequences of length 4 are:
%e A247386 ## [ ballot seq] ascent positions major index
%e A247386 01: [ 1 1 1 1 ] (none) 0
%e A247386 02: [ 1 1 1 2 ] 3 3
%e A247386 03: [ 1 1 2 1 ] 2 2
%e A247386 04: [ 1 1 2 2 ] 2 2
%e A247386 05: [ 1 1 2 3 ] 2 + 3 5
%e A247386 06: [ 1 2 1 1 ] 1 1
%e A247386 07: [ 1 2 1 2 ] 1 + 3 4
%e A247386 08: [ 1 2 1 3 ] 1 + 3 4
%e A247386 09: [ 1 2 3 1 ] 1 + 2 3
%e A247386 10: [ 1 2 3 4 ] 1 + 2 + 3 6
%e A247386 The sum of the major indexes is a(4) = 30.
%Y A247386 Cf. A232439.
%K A247386 nonn
%O A247386 0,4
%A A247386 _Joerg Arndt_ and _Alois P. Heinz_, Sep 15 2014