HOUSTON (AP) The number of rigs actively exploring for oil and natural gas in the U.S. rose this week by three, to 1,809. Texas-based oilfield services company Baker Hughes Inc. reported Friday that 1,390 rigs were exploring for oil and 417 were searching for gas. Two were listed as miscellaneous. A year ago, Baker Hughes counted 2,001 rigs. Of the major oil- and gas-producing states, Louisiana gained five rigs, Colorado three and California and West Virginia one each.Alaska, New Mexico, Oklahoma and Pennsylvania declined by two apiece and Texas and Wyoming each fell by one. Arkansas and North Dakota were unchanged.The rig count peaked at 4,530 in 1981 and bottomed at 488 in 1999.