Dozens of volunteers and staff workers are spending this weekend at inaugural committee headquarters addressing and stamping invitations to people who were inadvertently left off the list of those who should be invited to President-elect Jimmy Carter's inauguration festivities.

Invitations director Curt Moffat said that "a couple thousand" invitations to one of the six official inaugural parties would be mailed by Monday. The last day they could be sent with any assurance of reaching the recipients before the Jan. 20 inauguration.

The Washington Post reported Friday that numerous Carter campaign volunteers who should have received party invitations have not because lists were lost, names were not entered into the computer producing the master list of names, or other mix-ups.

Moffat, 29, said he and other committee officials met with Carter transition staff members Friday to compile a final list of people who should be sent invitations.

"When you're trying to coordinate this many lists, and names and there are so relatively few tickets, it's inevitable there will be mistakes," Moffat said. "We didn't know how many ball sites there were when we started soliciting lists, nor what the capacity of the parties would be, nor how many names we'd come up with all told. We expected to be mailing a second go-round at about this time."

The committee will have mailed 300,000 general invitations to Carter supporters and workers around the country. About 25,000 of these also will contain an invitation to buy two $25 tickets to an inaugural party, another 18,000 will be invited to buy a $25 ticket to watch the parade from a bleacher seat, and about 11,400 to buy a $25 ticket to attend one of two receptions for Vice-President elect Walter Mondale.

Discrepancies surfaced after people who were not invited started to complain. Other people are getting their invitations late because some lists were compiled late.

For example, staff members of the Democratic National Committee did not receive invitations until last week. Moffat said that happened because two lists of names were turned in at separate times and he thought the second list included the first list of names. Once the discrepancy involving 10 or 15 people, was discovered, he said, it was corrected.

The AFL-CIO turned in a list of the president and executive secretaries of its organizations in each state. Invitations were sent only to the presidents, not to the executive secretaries. Moffat said that "lack of understanding of AFL-CIO protocol" - not realizing that the executive secretaries were as important as the presidents - caused that problem.

In contrast to the people who cannot understand why they have not been invited to an inaugural party, there are some who cannot understand why they have received one of the general, souvenir invitations.

They include prisoners, children who wrote letters to Carter, and people who criticized Carter. Sonia Barton of Alexandria, for example, said all she ever did for Carter was to purchase for $2 eight campaign buttons for her collection. Since then she has received a glossy picture of the President-elect and now, an invitation to the inaugural.

Moffat said that a list was kept of everyone who expressed interest in Carter, including the children, the prisoners, and people such as Mrs. Barton, and that list was one of those fed into the computer.

At inaugural committee headquarters yesterday workers cordoned off with special security in one three rooms of one wing were busy typing addresses on envelopes, stuffing the various invitations into them and stacking them into bundles for mailing. A security guard posted at the entrance to the wing [TEXT OMITTED FROM SOURCE]