Numbers occurrence in list.

[Sunshine2020]

I have a list of numbers including 0 to 30. How to get the position (row number) for all 0 to 30 already appeared twice or three times in the list? I am working on to get one array formula to get the row number result into one cell. Also this worksheet should be worked in iPhone version Excel.

 

[Zot]

Here is a sample of array formula you can use

 

[Tetra201]

An interesting problem.

Assuming you have your 0 to 30 numbers in range A1:A1000, see if the following array formula works for you.
It returns the row number by which all 0 to 30 numbers have appeared at least twice.

=MAX(MATCH(COLUMN(INDIRECT("C1:C31",))-1,IF(MMULT(--(ROW($A$1:$A$1000)=MATCH(COLUMN(INDIRECT("C1:C31",))-1,$A$1:$A$1000,0)),SIGN(ROW(INDIRECT("R1:R31",)))),"",$A$1:$A$1000),0))

If you have the SEQUENCE function in your excel, here is a more compact version of the formula:

=MAX(MATCH(SEQUENCE(,31,0),IF(MMULT(--(ROW($A$1:$A$1000)=MATCH(SEQUENCE(,31,0),$A$1:$A$1000,0)),SEQUENCE(31,,1,0)),"",$A$1:$A$1000),0))

 

[Zot]

Looks like I did not understand the question properly

 

[Sunshine2020]

An interesting problem.

Assuming you have your 0 to 30 numbers in range A1:A1000, see if the following array formula works for you.
It returns the row number by which all 0 to 30 numbers have appeared at least twice.

=MAX(MATCH(COLUMN(INDIRECT("C1:C31",))-1,IF(MMULT(--(ROW($A$1:$A$1000)=MATCH(COLUMN(INDIRECT("C1:C31",))-1,$A$1:$A$1000,0)),SIGN(ROW(INDIRECT("R1:R31",)))),"",$A$1:$A$1000),0))

If you have the SEQUENCE function in your excel, here is a more compact version of the formula:

=MAX(MATCH(SEQUENCE(,31,0),IF(MMULT(--(ROW($A$1:$A$1000)=MATCH(SEQUENCE(,31,0),$A$1:$A$1000,0)),SEQUENCE(31,,1,0)),"",$A$1:$A$1000),0))

Thanks for your answers. It is a very brilliant idea for get the row number for appearing twice. Is it possible to extend it to find the row number by which all numbers have already appear three time or four time...?