48711domain: NAppears in sequencesNumbers k such that k^3 divides 17^(k^2) + 1.at n=26A177817Numbers n such that n^2 divides (17^n + 1).at n=17A292392a(n) = Sum_{j=1..n} Sum_{k=1..n} sigma(j*k).at n=16A372675E.g.f. satisfies A(x) = (1 + x)^3 * exp(x * A(x)).at n=5A377828