This is makeindex, version 2.15 [MiKTeX 2.9.7400 64-bit] (kpathsea + Thai support).
Scanning input file mathbook.idx....done (22 entries accepted, 0 rejected).
Sorting entries....done (102 comparisons).
Generating output file mathbook.ind....done (47 lines written, 0 warnings).
Output written in mathbook.ind.
Transcript written in mathbook.ilg.