Excluding same type of transactions within 3 seconds

For example, a table is like below

Type	Time Stamp	Result
1	2021-06-25 14:21:00	A
1	2021-06-25 14:21:03	B
1	2021-06-25 14:21:06	C
1	2021-06-25 14:23:00	D
2	2021-06-25 14:21:02	C
2	2021-06-25 14:21:06	C
2	2021-06-25 14:21:09	D
3	2021-06-25 14:21:06	E

And the result I want is as below. If there are a series of transactions with the same type every 3 seconds or less, I will print the last one only.

Type	Time Stamp	Result
1	2021-06-25 14:21:06	C
1	2021-06-25 14:23:00	D
2	2021-06-25 14:21:02	C
2	2021-06-25 14:21:09	D
3	2021-06-25 14:21:06	E

Answer

Simplifying Gordon’s query using a default for LEAD and Teradata’s proprietary QUALIFY keyword:

select *
from vt
qualify 
   lead(timestamp, 1, date '9999-12-31')
   over (partition by type
         order by timestamp) > timestamp_ + interval '3' second;