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.
Table[DivisorSigma[n^2, n], {n, 1, 10}] (* Vaclav Kotesovec, Jun 08 2019 *)
{a(n) = sigma(n, n^2)}
Square array begins: 1, 1, 1, 1, ... 3, 5, 17, 257, ... 4, 28, 19684, 7625597484988, ... 9, 273, 4294967553, 340282366920938463463374607431768276993, ...
T[n_, k_] := DivisorSum[n, #^(n * #^(k-1)) &]; Table[T[k, n - k], {n, 1, 7}, {k, 1, n}] // Flatten (* Amiram Eldar, May 09 2021 *)
a[n_] := DivisorSum[n, #^(#^2) &]; Array[a, 8] (* Amiram Eldar, May 11 2021 *)
{a(n) = sumdiv(n, d, d^d^2)}
N=20; x='x+O('x^N); Vec(x*deriv(-log(prod(k=1, N, (1-x^k)^(k^(k^2-1))))))
Table[Total[#^(#^2 n)&/@Divisors[n]],{n,5}] (* Harvey P. Dale, Feb 29 2020 *)
a[n_] := DivisorSum[n, #^(n * #^2) &]; Array[a, 5] (* Amiram Eldar, May 11 2021 *)
{a(n) = sumdiv(n, d, d^(d^2*n))}
N=10; x='x+O('x^N); Vec(x*deriv(-log(prod(k=1, N, (1-(k^k^2*x)^k)^(1/k)))))
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