Another Sequence - Teaser 8

What's the next letter in this series?

   H, H, L, B, B, C, N, O, F, N

Hint

1834 — 1907

Answer

   S

Explanation

These are the first letters of the English names of the first few elements (based on their atomic number): Hydrogen, Helium, Lithium, Beryllium, Boron, Carbon, Nitrogen, Oxygen, Fluorine, Neon ... and, of course, Sodium.  Dmitri Mendeleev, born on 27 January 1834, published his Periodic Table of Elements in 1860.