How to merge results of the arrays in PgSQL

Assuming I have two fields in a table, like this:

Column | Type |
--------+-----------+
id | integer |
value | integer[] |


SELECT * FROM t1;
id | value
----- +-----------------------------------
1 | {1, 2, 3}
2 | {1, 4}
3 | {1, 5}

How would I make a query which returns a array, returned the merged the t1.values, i.e. something like:

SELECT some_array_function(value) as newarray FROM t1;
new_array
--------------------------------
{1, 2, 3, 4, 5}


Thanks!

Thanks!