The phrase "a sparse number" is correct and usable in written English.
It can be used to describe a quantity that is limited or insufficient in a particular context.
Example: "In the survey, we received a sparse number of responses, making it difficult to draw any conclusions."
Alternatives: "a limited number" or "a small number".
Oil prices have also been traditionally higher in the Northeast than in much of the rest of the country, because of a high demand and a sparse number of large refineries.
Crystallin gene expression in lens is regulated at the level of transcription by a sparse number of specific DNA-binding transcription factors.
Michael Paoletta from Billboard described the song as a "sparse number" and said that it was a "good fit" for the radio.
In contrast, unfamiliar objects entailed a sparse number of only unidirectional connections converging to parietal areas.
The areas M and A are affected with PWD since 2008 and include mainly P. pinaster, with a sparse number of P. radiata, Quercus and Eucalyptus trees.
While this data would suggest that DNA CpG methylation is involved with the regulation of expression of the CXC receptors and CXCL8, a search of the UCSC genome library (http://genome.ucsc.edu/) revealed a sparse number of CpG residues at the promoter regions of these three genes.
In the sparse model, each datum (signal) can be approximated by the linear combination of a small (sparse) number of elementary signals, called atoms, from a pre-specified basis or frame, called dictionary.
Though several other vocabularies and grammatical sketches followed, that century and the next saw a rather sparse number of works on African languages.
Also a bigger sparse number K will expose the sidelobes of the reconstruction, and Fourier interpolation can be applied into evaluating the imaging results.
39 This technique identified a relatively sparse number of motor units (∼14) in both SMNΔ7 and control soleus muscles.
Expression filters (i.e., the levels of expression of the proteins) were not used as they resulted in a very sparse number of small subnets.
