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Versatile Formula to Generate a Unique List of Numbers
Excel 365 Formula to Generate a Unique List of Numbers
=CONCATENATE(
DEC2HEX(RANDBETWEEN(0,4294967295),8),"-",
DEC2HEX(RANDBETWEEN(0,65535),4),"-",
DEC2HEX(RANDBETWEEN(16384,20479),4),"-",
DEC2HEX(RANDBETWEEN(32768,49151),4),"-",
DEC2HEX(RANDBETWEEN(0,65535),4),
DEC2HEX(RANDBETWEEN(0,4294967295),8))
=IFERROR(LARGE(ROW($100:$999)*NOT(COUNTIF($C$6:C6,ROW($100:$999))),RANDBETWEEN(1,999-100-ROW(A1)+2)),"")
Min 100
Max 999
Range $C$6:C6
Change the Min value to the lowest possible value that you want to appear in the list. Change all occurrences of this number in the formula.
Change the Max value to the highest possible value that you want to appear in the list. Change all occurrences of this number in the formula.
Change the Range to the address of the first cell above the start of the list. Keep the exact format that it has now, with the first part in absolute references (with $ signs) and the second part in relative references.
Number of values is controlled by copying this formula down the column. Get the formula correct for the first entry and then copy it down as many times as you need to get as many unique random numbers as you need.
=INDEX(UNIQUE(RANDARRAY(10^2,1,100,999,TRUE)),SEQUENCE(10))
Min 100
Max 999
Number of Values 10
Change the Min value to the lowest possible value that you want to appear in the list.
Change the Max value to the highest possible value that you want to appear in the list.
Change the Number of Values to the number of values that you want to appear in the list. Change every bold occurrence of 10 in the formula.
This generates a simple integer list of values that moves sequentially up or down.
=SORTBY(SEQUENCE(10),RANDARRAY(10))
Number of items to show is controlled by the number in the formula. Change 10 in both places to however many items you want to show.
This works for all versions of Excel.