The Commerce Department's Bureau of Economic Analysis has put into use the first of four telephone numbers the public can call any hour of the day to get recorded information on major economic statistics.

Precisely at 8:30 a.m. on Dec. 3, a four-minute recording with details of the index of leading indicators for October was available on the 12 lines reached by dialing 898-2450, a spokesman said.

The recording includes the levels and percentage changes for the latest three months for the leading indicators and the contribution that changes in each of the dozen statistical series made to the overall index in October.

On Dec. 19, an all-purpose number, 898-2453, will be used to provide details on the latest quarterly survey of business intentions to invest in new plants and equipment in 1986. Later, that number also will carry information on two other quarterly statistics, merchandise trade on a balance-of-payments basis and U.S. international transactions.

On Dec. 20, a third number, 898-2451, will be activated to handle the gross national product figures released that morning. The so-called "flash" estimate for the current quarter and the second revision of the third-quarter figures will be covered.

On Dec. 23, details of personal income and outlays for November will be made available on 898-2452.