207576

Appears in sequences

• Prime power perfect numbers: If n = Product p_i^r_i let PPsigma(n) = Product {Sum p_i^s_i, 2<=s_i<=r_i, s_i is prime}; sequence gives numbers k such that PPsigma(k) = 2*k.at n=9A096290
• Numbers with prime factorization p^2*q^3*r^3 where p, q, and r are distinct primes.at n=21A190106
• Powerful numbers (A001694) which can be written as the sum of two relatively prime 3-powerful numbers (A036966) different from 1.at n=15A210470
• Powerful numbers of the form x^3 + y^3 with x and y coprime.at n=4A238120
• Product_{n>=1} 1 + a(n)*x^n = Sum_{n=-oo..oo} x^(n^2) = theta_3(x).at n=21A342223