Array formula in B12:

=INDEX(tbl, MIN((IF((COUNTIF($B$11:B11, tbl)=0)*(LEFT(tbl, LEN($D$9))=$D$9), ROW(tbl)-MIN(ROW(tbl))+1))), MATCH(0, COUNTIF($B$11:B11, INDEX(tbl, MIN(IF((COUNTIF($B$11:B11, tbl)=0)*(LEFT(tbl, LEN($D$9))=$D$9), ROW(tbl)-MIN(ROW(tbl))+1)), , 1))+(LEFT(INDEX(tbl, MIN(IF((COUNTIF($B$11:B11, tbl)=0)*(LEFT(tbl, LEN($D$9))=$D$9), ROW(tbl)-MIN(ROW(tbl))+1)), , 1), LEN($D$9))<>$D$9), 0), 1) + CTRL + SHIFT + ENTER copied down as far as needed.

Named ranges

tbl (B3:D5)
What is named ranges?

How to implement array formula to your workbook

Change the named range and "begins with" cell reference ($D$9). If your list starts at, for example, F3. Change $B$11:B11 in the above formulas to F2:$F$2.

Download excel sample file for this article.

Extract unique distinct values begins with A in a range.xls
(Excel 97-2003 Workbook *.xls)

Final notes

I don´t think this can be done with a range using pivot table, if so please comment.

Functions in this article

ROW(reference) Returns the rownumber of a reference

COUNTIF(range,criteria)
Counts the number of cells within a range that meet the given condition

IF(logical_test;[value_if:true];[value_if_false])
Checks whether a condition is met, and returns one value if TRUE, and another value if FALSE

MATCH(lookup_value;lookup_array; [match_type]
Returns the relative position of an item in an array that matches a specified value

INDEX(array,row_num,[column_num])
Returns a value or reference of the cell at the intersection of a particular row and column, in a given range

MIN(number1,[number2])
Returns the smallest number in a set of values. Ignores logical values and text

LEFT(text;num_chars) Returns the specified number of characters from the start of textstring

LEN(text)
Returns the number of characters in a text string

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