Number of relatively prime or monic twice-partitions of n.

Terms

a(0) =1a(1) =3a(2) =6a(3) =10a(4) =27a(5) =35a(6) =113a(7) =170a(8) =396a(9) =641a(10) =1649a(11) =2318a(12) =5905a(13) =9112a(14) =18678a(15) =32529a(16) =69094a(17) =106210a(18) =227480a(19) =363433a(20) =705210a(21) =1196190a(22) =2325023a(23) =3724233a(24) =7192245a(25) =11915884a(26) =21857887a(27) =36597843a(28) =67406158a(29) =109594872