Or simpler, H\d+. \d* will match *zero* or more digits, \d+ matches *one* or more.

update: oh, wait, ignore me. You need to knock out the H in (eg) NaOH, which doesn't have a digit after it.

In reply to Re^5: How to avoid an alphabet and integer next to it in a string? by DrHyde
in thread How to avoid an alphabet and integer next to it in a string? by piscean

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