102152

Appears in sequences

• Numbers k such that phi(k)^2+sigma(k)^2 is prime.at n=36A068367
• Numbers n for which the absolute value of the abundance of both n and n^2 is a prime number.at n=22A125237
• Members of A143610 for which both neighbors are squarefree.at n=25A166987
• Number of 2 X 2 matrices having all elements in {0,1,...,n} and determinant = 0 (mod 3).at n=21A211033
• Nontotients (A005277) that are the product of two totients (A002202).at n=38A329872