By John S. McClenahen "Ugly." That was Merrill Lynch & Co. Chief Economist Bruce Steinberg's description of last Friday's reported January rise in the "core" producer price index (PPI). The January consumer price index (CPI) numbers due out Feb. 21 are expected to show some acceleration of inflation, but nothing like the PPI's rise. Merrill Lynch figures the overall CPI rose three tenths of a percentage point last month, with the "core" (the index excluding energy and food) up 0.2 of a percentage point. Salomon Smith Barney Inc., a unit of Citigroup Inc., New York, isn't quite as sanguine. It's expecting a 0.5 percentage point increase in the overall CPI and a 0.3 rise in the core index.