How to convert a column number into another column cell

[ahmedo047]

Dear users,

A column:
18
42
55
11
65
72
80
48
..
I want to put/write to B column the some numbers (42,11,72,48..) in A column.
B column:
=A2
=A4
=A6
=A8
..
How can I achieve it?

[Max, Singapore]

One way
Assume your data runs in A1 down
Put in B1: =INDEX(A:A,ROW()*2)
Copy down
------------------------
Any good? Wave it, click on the little star at the bottom left of my responses

[ahmedo047]

It is giving error:
We found a problem with this formula. Try clicking Insert Function .....

[Max, Singapore]

It may be the Excel version you are using ?
Try changing the comma in the formula to a semi colon, viz: =INDEX(A:A;ROW()*2)
My excel uses commas as separators

[ahmedo047]

Last command works. Sorry I asked the wrong question. I want to put/write to B column the some numbers (42,65,80,95,,,) in A column.
A B
18 42
42 65
55 80
11 95
65
72
80
48
95
102

[Max, Singapore]

What is the logic behind the selection of those numbers? Perhaps you could explain

[ahmedo047]

I have to select A2,A5,A7,A9,A11..... There is a steady increase after first selection.

[Max, Singapore]

Try this then ...
In B1: =A2
In B2: =INDEX($A$4:$A$1000,ROWS($1:1)*2)
Copy B2 down. Modify the $A$1000 to suit the extent of your data

[ahmedo047]

you are wonderful. Thanks. It works.

[Max, Singapore]

welcome, glad it worked for you

[ahmedo047]

Sorry last question:
If I have to select A1249,A2501,A3753,A5005,A6257..... how can I achieve it?

[Max, Singapore]

You could use this in say B1: =INDEX($A$1249:$A$10000,ROWS($1:1)*1252-1251)
Copy down

[ahmedo047]

Thank you very much. It works