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 A370359 #6 Feb 16 2024 15:21:41
%S A370359 0,1,8,54,0,-12500,-373248,-6588344,0,6198727824,320000000000,
%T A370359 9129973459552,0,-19384006821904192,-1422336873671426048,
%U A370359 -56050417968750000000,0,211773507042902211629312,20145360934551827238617088,1012950863698080557631477248,0,-5982809106827246101894271407104
%N A370359 Imaginary part of (n + n*i)^n where i = sqrt(-1).
%F A370359 a(n) = n^n*A009545(n) = n^n*Sum_{j=0..floor((n-1)/2)} binomial(n,2*j+1)*(-1)^j.
%F A370359 a(n) = 0 if and only if n == 0 mod 4.
%F A370359 a(4n) = 0.
%F A370359 a(4n+1) = (4n+1)^(4n+1)*(-4)^n.
%F A370359 a(4n+2) = 2*(4n+2)^(4n+2)*(-4)^n.
%F A370359 a(4n+3) = 2*(4n+3)^(4n+3)*(-4)^n.
%o A370359 (Python)
%o A370359 def A370359(n): return n**n*((0, 1, 2, 2)[n&3]<<((n>>1)&-2))*(-1 if n&4 else 1)
%o A370359 (PARI) a(n) = imag((n + n*I)^n); \\ _Michel Marcus_, Feb 16 2024
%Y A370359 Cf. A009545, A121625, A146559.
%K A370359 sign
%O A370359 0,3
%A A370359 _Chai Wah Wu_, Feb 16 2024