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 A174881 #19 Oct 13 2024 17:41:36
%S A174881 2,36,1728,160000,24300000,5489031744,1727094849536,722204136308736,
%T A174881 387420489000000000,259374246010000000000,211988959518950443450368,
%U A174881 207728067204059288762843136,240396446553194784543350546432,324391993252150868100000000000000
%N A174881 a(n) = n^n * (n+1)^n.
%C A174881 a(n) is the number of ordered pairs of maps i; j : {1, 2, 3, ..., n} --> {1, 2, 3, ..., n, L, R} where neither map has fixed points and both maps are distinct at every point. See p. 18 of Dimofte. In Kontsevich, these are called admissible graphs.
%D A174881 M. Kontsevich, Deformation quantization of Poisson manifolds, Lett. Math. Phys. 66 (2003), no. 3 157-216, [q-alg/9709040v1].
%H A174881 Paolo Xausa, <a href="/A174881/b174881.txt">Table of n, a(n) for n = 1..200</a>
%H A174881 Tudor Dimofte, Sergei Gukov, <a href="https://doi.org/10.48550/arXiv.1003.4808">Quantum Field Theory and the Volume Conjecture</a>, arXiv:1003.4808 [math.GT], 2010.
%F A174881 a(n) = (n^n)*((n+1)^n) = (n*(n+1))^n = A000312(n)*A000169(n+1).
%e A174881 a(1) = (1^1)*((1+1)^1) = 2.
%e A174881 a(2) = (2^2)*((2+1)^2) = 36.
%e A174881 a(3) = (3^3)*((3+1)^3) = 1728.
%e A174881 a(4) = (4^4)*((4+1)^4) = 160000.
%e A174881 a(5) = (5^5)*((5+1)^5) = 24300000.
%t A174881 Table[(n*(n + 1))^n, {n, 15}] (* _Paolo Xausa_, Oct 13 2024 *)
%Y A174881 Cf. A000169, A000312.
%K A174881 easy,nonn
%O A174881 1,1
%A A174881 _Jonathan Vos Post_, Mar 31 2010