Growth factor is any of about twenty small proteins that function
is to attach to specific receptors on the surface of stem cells in
bone marrow and promote differentiation and maturation of these cells
into morphotic constituents of blood.
... such that:
<math> \sum_{k=1}^\infty{1\over p_{i+k}} < {1 \over 2}</math>
Define N(x) as the number of positive integers n not exceeding x and not ...