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

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =1a(5) =3a(6) =15a(7) =28a(8) =69a(9) =111a(10) =259a(11) =336a(12) =671a(13) =906a(14) =1355a(15) =1769a(16) =2961a(17) =3461a(18) =5438a(19) =6501a(20) =8613a(21) =10371a(22) =15022a(23) =16807a(24) =22759a(25) =26512a(26) =33090a(27) =37822a(28) =50603a(29) =54583