Number of proper divisors of the Catalan number A000108(n).

Terms

a(0) =0a(1) =0a(2) =1a(3) =1a(4) =3a(5) =7a(6) =11a(7) =7a(8) =15a(9) =15a(10) =23a(11) =31a(12) =47a(13) =71a(14) =191a(15) =95a(16) =191a(17) =255a(18) =575a(19) =511a(20) =767a(21) =767a(22) =1023a(23) =1151a(24) =1151a(25) =1727a(26) =1535a(27) =1535a(28) =4095a(29) =4095