What was going on when I was born?

A Federal appeals court today struck down a key section of New York State's tax on oil company receipts. But it implied the statute might withstand Federal challenge after September, when Federal price controls on petroleum expire. The decision, issued in Washington by the Temporary Emergency Court of Appeals, immediately threw into disarray the Legislature's negotiations on aid to mass transit. The oil tax, enacted last year, was intended to provide $235 million a year for public transportation, most of it for the Metropolitan Transportation Authority.

Matthew Volz, 6, and his sister, Charissa, 2, helping Chief Warrant Officer Wayne Devoe conduct the U.S. Marine Band during Flag Day ceremonies yesterday at the World Trade Center. The children, from Canton, Mich., are visiting New York with their parents.

''The Constitution does not mandate comfortable prisons.'' - Associate Justice Lewis F. Powell Jr. (B9:1.)

Czeslaw Milosz, exiled poet, is national hero on return to Poland A2 West critical of East Berliners' voting for Parliament A4 Around the World A5 Gromyko presses U.S. on starting arms control talks A6 Israeli aides in U.S. bemoan Reagan policy A7 Peres complains about violence in Israeli campaign A8 Survivors of Nazi terror mingle in joy and sorrow A9 Philippines expelling a U.S. priest A12 Kenya urges Africans to step up aid to Namibian guerrillas A15 Government/Politics Appeals court upsets ruling for Detroit on census A16 Koch vs. Kheel: where is the challenger headed? B1 Suit opposes moving Navy office into fort on Staten Island B2 State and Westchester agree to let the Air National Guard move B3 Republicans push attack on Democrats' budget cuts B10 House action near on disputed Federal legal-aid program B10 Reagan urges mayors to support block grant proposal B11 Reagan asks for study of Voting Rights Act impact B11 F.B.I. computerized index of states' crimes to be urged B13 Board approves $185 million for foster care agencies B19 General Around the Nation A16 Dover, Del. has an excess of parks A16 Polluted air plagues Phoenix, surprising many A16 Many tenured teachers losing their jobs in the New York area B2 Bus carrying group seeking jobs for minorities is attacked B3 High Court refuses to hear appeal on city police test B4 Pretrial hearing set on officer's tie to Soviet B12 Science Times From jungle outpost, Europeans ready a space challenge C1 Government scrutinizes gene industry link to universities C1 Studies suggest feminism may play mental health role C1 Education: City College cultivates minority engineers C1 Science Watch C2 The Doctor's World: Pope recovery reflects modern advances C2 Moth evolves jamming device to thwart bat C3 About Education: A warning on decline in teacher training C4 Science Q&A C2 Industry/Labor A.P. and unions continue to talk through strike deadline B6 Oil, Chemical and Atomic Workers in leadership battle B12 Arts/Entertainment Balanchine's new ''Pathetique'' danced by City Ballet C7 PG rating for ''Raiders of the Lost Ark'' is questioned C7 ''Sleeping Beauty'' opens Royal Ballet's 50th season C8 Baryshnikov's ''Don Quixote'' danced with three casts C8 Steve Lawrence and Eydie Gorme in Carnegie Hall concerts C8 Study of medieval need for monsters is reviewed C9 ''Cities in China,'' TV film, tours Suzhou and its gardens C19 Presidential task force on arts told to do more with less C20 Style Notes on Fashion B14 A fashion market in lustrous metal B14 Lee Wright wins design prize B14 Obituaries John G. Dinkeloo, innovative architect B19 Sports Baseball talks resume today, but outlook is pessimistic B15 Charlie Sanders adapts to life without football B15 Jersey interscholastic leagues can exclude private schools B15 Cabanas showing his full talent for the Cosmos B15 George Vecsey on object lessons of baseball strike B17 Backman of Mets carries strike to minors B17 Features/Notes Notes on People B18 News Analysis Richard Eder assesses Socialist victory in France A3 E. J. Dionne Jr. on New York State property tax impasse B20 Editorials/Letters/Op-Ed Editorials A18 What kind of defense? Police spread thin Cold-stove league Letters A18 Sydney H. Schanberg: the cupidity lobby A19 Tom Wicker: unwelcome personal testimony A19 A. Bartlett Giamatti: men of baseball, lend an ear A19 Catherine Lerza: new farmers need aid A19

Britain agreed today to cut the price of oil from the North Sea by $4.25 a barrel, more than double its earlier intention and a further sign of the intense downward pressure on world oil prices. The price of the most plentiful grade of North Sea oil would fall to $35 a barrel. That is as much as $6 a barrel below prices charged by Algeria, Nigeria and Libya, the three highest-priced producers, for oil of comparable quality. As a result, oil experts believe, those three producers, which are major exporters to the United States, will be forced to reduce their prices.

President Reagan, opening a personal lobbying campaign for his three-year program of tax cuts, won the endorsement of key Democrats in the Senate today, but he found that some of his allies were making plans for minor changes in his legislation. Democrats and Republicans alike predicted, for example, that Mr. Reagan might have to accept additional tax breaks to help rescue the nation's faltering savings and loan industry by reducing taxes on income from savings. ''I would assume there'll be some modification,'' said Senator Russell B. Long, the Louisiana Democrat who is ranking minority member of the Finance Committee. Mr. Long said he expected to vote for Mr. Reagan's three-year, 25 percent tax cut rather than the original Democratic proposal of a 15 percent cut over two years. The President, meanwhile, made plans to hold his first news conference in three and a half months at 2 P.M. tomorrow. His aides acknowledged that Mr. Reagan's intention of focusing on economic issues could be disrupted by questions on other topics, such as Israel's bombing of an Iraqi nuclear reactor.

President Reagan won endorsements for his three-year tax cut program from key Senate Democrats as he began a personal lobbying effort. Yet some allies favored small changes in the plan, such as additional cuts in the tax on savings income to help the savings and loan industry. (Page A1.) The Chemical Bank reduced its prime rate to 19 percent from 20 percent. Although other banks did not immediately follow suit, many bankers predicted interest rates would continue to drop, at least through the summer. (D1.)

PRESIDENT'S SHOW By MAURICE CARROLL Former President Richard M. Nixon last night made his first public appearance at a New York City political event since he left the White House and was warmly welcomed at a Republican fund-raising party at Lincoln Center. Mayor Koch was there, too, in the first redemption of his pledge to help Republicans raise money since they voted to let him run for re-election in their primary. The two politicians did not cross paths. The Mayor hurried out to another party before the former President arrived. It didn't matter for the crowd of 1,500 or so at the $200-a-plate Republican State Committee reception in the New York State Theater lobby. Mr. Nixon was the one they wanted to see.

International A $3 billion aid program for Pakistan was announced by the State Department. It said that the economic and military assistance would bolster Pakistani defenses against a ''serious threat'' from Soviet troops in Afghanistan. The Carter Administration suspended aid to Pakistan in April 1979 because Pakistan refused to submit its nuclear development program to international inspection. (Page A1, Col. 6.) Israel was censured by France and Britain in the United Nations Security Council for the air attack on an Iraqi nuclear reactor. But the two Western European countries, both permanent council members with veto power, declined to back an Arab demand for an arms embargo. (A1:3.)

United States business inventories grew by five-tenths of 1 percent in April as sales by the nation's manufacturers, wholesalers and retailers slipped slightly, the Commerce Department reported today. The report was consistent with other recent statistics showing a sluggish national economy, which has slowed substantially in the second quarter after its recovery from last year's recession, but which is apparently not heading for a sharp new downturn. The Commerce Department also reported a downturn in total business sales in April. The drop was $434 million, or about one-tenth of 1 percent, to $346.15 billion. All of the decline was registered by durable goods industries.

Next month, an armada of tugs and barges will leave Puget Sound for the two-and-a-half-week voyage north through the Gulf of Alaska, past the Aleutian chain, across the Bering Sea, around Point Barrow and to the docks at Prudhoe Bay. Aboard will be multimillion-dollar cargoes of oilfield equipment that will permit the extraction from the rich Alaskan fields of as much oil as possible. The prime oil formation in Prudhoe Bay is the Sadlerochit, where production started in 1977 from sandstone that begins at 9,000 feet below the frozen mud on the surface. A secondary discovery, where production is expected to start early next year, lies slightly above, at 7,500 feet, and to the west, in the Kuparuk formation.

The Supreme Court ruled today that two prisoners may be confined in a cell designed for only one as long as the overall prison conditions do not violate a ''contemporary standard of decency.'' The 8-to-1 decision overturned rulings by two Federal courts in Ohio, where 1,400 inmates at the state's maximum security prison were required to double up in 63-square-foot cells designed to house one person. In another case dealt with today, the Court unanimously upheld the constitutionality of the Federal strip mining law as Interior Secretary James G. Watt was taking action to cut back the staff of the agency that is charged with enforcing it. (Page B9.)