Are there gaps in the 2% resistor standard values?
Resistors are not made to random value and then sorted, they are manufactured to be close to the desired value ( a bit lower)  and then trimmed with cutters, abrasive or laser trimming) into the final value (sometimes a bit high, depending on the process), typically well within tolerance (typical error is usually less than 1/3 of the guaranteed tolerance, last I measured a bunch. 

So the gaps due to rounding or whatever in the standard series are of no consequence to the manufacturers. 

As such, you can get much closer than you might expect, most of the time, to the desired value by paralleling or putting in series standard values to make the nominal value very close to the exact value you want.