Number of ordered 5-tuples of integers from [ 1,n ] with no common factors among quadruples.

Terms

a(0) =1a(1) =4a(2) =15a(3) =36a(4) =95a(5) =162a(6) =345a(7) =555a(8) =942a(9) =1376a(10) =2277a(11) =3049a(12) =4694a(13) =6216a(14) =8560a(15) =11077a(16) =15491a(17) =18956a(18) =25626a(19) =31254a(20) =39682a(21) =47942a(22) =61624a(23) =71912a(24) =89989a(25) =105658a(26) =127911a(27) =148410a(28) =181397a(29) =204777