Three Prudential Investments sector funds have proven popular with investors in their 31-day initial offering period. The Prudential Technology Fund, Health Sciences and Financial Services funds collectively attracted almost $400 million in the first month. Each fund divides assets equally into a concentrated portfolio of between 20 and 40 stocks and an enhanced index portfolio. The funds are Prudentials second-most-popular equity offerings, said company officials, who noted that only the Prudential 20/20 Fund, introduced in 1998, attracted more assets ($900 million) in less than a year. The Prudential Tax-Managed Equity Fund isnt far behind, having received more than $320 million since inception.