221370

Appears in sequences

• The smallest pronic (A002378) that contains the digits of n in its exact middle.at n=13A163597
• G.f. A(x) satisfies: A(x - x*A(x)) = x + x*A(x).at n=7A276358
• a(n) is the position of A051451(n) in A025487.at n=25A346407