a(1)=1, a(2)=2, a(n)=a(n-1)+floor(a(n-2)*a(n-1)/(a(n-2)+a(n-1))).

Terms

a(0) =1a(1) =2a(2) =2a(3) =3a(4) =4a(5) =5a(6) =7a(7) =9a(8) =12a(9) =17a(10) =24a(11) =33a(12) =46a(13) =65a(14) =91a(15) =128a(16) =181a(17) =255a(18) =360a(19) =509a(20) =719a(21) =1017a(22) =1438a(23) =2033a(24) =2875a(25) =4065a(26) =5748a(27) =8129a(28) =11496a(29) =16257