Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
Which sum of week that had an attendance larger than 55,767 on September 28, 1986?

### Inputs:
table_name: table, columns: ['Week', 'Date', 'Opponent', 'Result', 'Attendance']

### Response:
SELECT SUM Week FROM table WHERE Attendance > 55,767 AND Date = september 28, 1986