Number of ordered 6-tuples (a,b,c,d,e,f) with gcd(a,b,c,d,e,f)=1 (1<= {a,b,c,d,e,f} <= n).

Terms

a(0) =1a(1) =63a(2) =727a(3) =4031a(4) =15559a(5) =45863a(6) =116855a(7) =257983a(8) =526615a(9) =983583a(10) =1755143a(11) =2935231a(12) =4776055a(13) =7407727a(14) =11256623a(15) =16498719a(16) =23859071a(17) =33434063a(18) =46467719a(19) =62949975a(20) =84644439a(21) =111486599a(22) =146142583a(23) =187854119a(24) =240880239a(25) =303814503a(26) =382049919a(27) =473813703a(28) =586746719