"RagDyeR" wrote:
.. Therefore, my hat is off to Harlan if he can accomplish this scenario
*without* the existence of this 40 column by 10 row array of random
numbers.

Think Harlan did accomplish this a few years back ? <g
(and in a very concise set-up, too !)
re his response at: http://tinyurl.com/b2oan

Here's an adaptation of Harlan's solution to the
OP's pick 6 out of 40 case

Define* a name: LottoNumbers
referring to: =ROW(INDIRECT("1:40"))
*via Insert Name Define

Then in A1 enter the formula:
=INT(1+COUNT(LottoNumbers)*RAND())

In B1, enter the array formula:
=LARGE(IF(COUNTIF($A1:A1,LottoNumbers),0,LottoNumb ers),
INT(1+(COUNT(LottoNumbers)-COUNT($A1:A1))*RAND()))

Copy B1 to F1

Select A1:F1, fill down to say, F10

A1:F10 will return 10 sets of 6 numbers (from 1-40)
w/o duplicates in any one set

Press F9 to recalc
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Rgds
Max
xl 97
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xdemechanik
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