68638

Appears in sequences

• Numbers k such that sigma(k) = sigma(k+5).at n=20A015865
• Numbers whose least quadratic nonresidue (A020649) is 19.at n=30A025027
• a(n) = [x^n] Product_{k=1..n} (x^(k^4) + 1/x^(k^4)).at n=40A368206