a(n) is the smallest positive integer k such that d(k) = d(k+2*n) = 2*n, where d(m) (A000005) is the number of positive divisors of m, or 0 if no such k exists.
A139416
a(n) is the smallest positive integer k such that d(k) = d(k+2*n) = 2*n, where d(m) (A000005) is the number of positive divisors of m, or 0 if no such k exists.
Terms
- a(0) =3a(1) =6a(2) =12a(3) =70a(4) =600281a(5) =60a(6) =1458a(7) =264a(8) =450a(9) =266875a(11) =480a(13) =11968722a(14) =299538a(15) =3640a(17) =1980a(19) =14960a(23) =6552
External references
- oeis: A139416