40633

Appears in sequences

• G.f.: A(x) = Sum_{n>=0} x^n*A(x)^(3*n*2^n/2).at n=6A177403
• Digits of composite k start as k', where k' is the arithmetic derivative of k.at n=1A375801
• a(n) = the smallest positive integer that produces a product that contains the digit 2 when multiplied by 2 at most n times, and where a further multiplication by 2 produces a number that does not contain the digit 2. Set a(n) = -1 if no such number exists.at n=22A381183