Smallest k such that tau(n + k) = tau (nk), or 0 if no such number exists, where tau = A000005.

Terms

a(0) =2a(1) =1a(2) =5a(3) =2a(4) =3a(5) =134a(6) =3a(7) =4a(8) =11a(9) =2a(10) =3a(11) =548a(12) =2a(13) =1a(14) =3a(15) =2a(16) =5a(17) =402a(18) =2a(19) =316a(20) =1a(21) =38a(22) =3a(23) =1236a(24) =3a(25) =1a(26) =13a(27) =2a(28) =5a(29) =1986