Zarankiewicz's problem k_4(n).A006616Zarankiewicz's problem k_4(n).Terms a(0) =16a(1) =23a(2) =32a(3) =43a(4) =52a(5) =62a(6) =75a(7) =87a(8) =101a(9) =118External referencesoeis: A006616