Zarankiewicz's problem k_3(n,n+1).A006621Zarankiewicz's problem k_3(n,n+1).Terms a(0) =11a(1) =17a(2) =23a(3) =30a(4) =38a(5) =46a(6) =55a(7) =65a(8) =75a(9) =87External referencesoeis: A006621