Change the value to 2 digits

Thank you, the formula matches what I expected.

Could you help with a few more formulas?

For example, if C9 is filled with the value 19, then cell C10 will result in 01*09*10*11*12*13*14*15*16*17*18*19*21*29*31*39*41*49*51*59*61*69*71*79*81*89*90*91*92*93*94*95*96*97*98*99, where C10 comes from C2 which has been trimmed.

I tried to change the value in cell C2 to 0125689, the result in cell C3 is correct, but when I try to fill in cell C9 with the value 38, it produces 01*09*11*19*21*29*30*31*32*33*34*35*36*37*38*39*41*49*51*59*61*69*71*79*80*81*82*83*84*85*86*87*88*89*91*99, it should have produced 08*18*28*58*68*80*81*82*85*86*88*89*98.

The value of C9 is a trimmed value generated from cell C3, the value of C9 can vary according to requirements.
reference https://katadata.org/live/index.php

Why not this?

=textjoin("*",1,reduce("",sequence(10,1,0),lambda(x,y,vstack(x,if(isnumber(find(y,trim(C3))),byrow(sequence(10,1,0),lambda(z,y&z)),vstack(y&"1",y&"9"))))))

The formula needs to be placed in cell?

Yes - its a formula, not code.

Is there a formula to trim cell C3 if it contains a value?

For example, if C2 contains a value and results in 11*12*15*16*18*19*21*22*25*26*28*29*51*52*55*56*58*59*61*62*65*66*68*69*81*82*85*86*88*89*91*92*95*96*98*99

Then if C9 is filled with the value 38, C10 will result in 08*18*28*58*68*80*81*82*85*86*88*89*98

The values in cells C2 and C9 can change according to needs.

Yes - I have included it in the big formula:

=TRIM(C3)

Why don't you provide a link to your GoogleSheet so that we can see what's going on?

Please stop quoting unnecessarily.

No - that's an Excel workbook.

Provide a LINK to your GoogleSheet online.

In C3:

=TEXTJOIN("*",1,REDUCE("",SEQUENCE(10,1,0),LAMBDA(x,y,VSTACK(x,IF(ISNUMBER(FIND(y,TRIM(C2))),BYROW(SEQUENCE(10,1,0),LAMBDA(z,y&z)),VSTACK(y&"1",y&"9"))))))

In C10:

=TEXTJOIN("*",1,REDUCE("",SEQUENCE(10,1,0),LAMBDA(x,y,VSTACK(x,IF(ISNUMBER(FIND(y,TRIM(C9))),BYROW(SEQUENCE(10,1,0),LAMBDA(z,y&z)),VSTACK(y&"1",y&"9"))))))

Or copy cell C10 (CTRL+C) and paste it to C3 (CTRL+V) and the cell reference will change automatically.

I've updated your GoogleSheet as well.

Change ALL references. In C3:

=let(a;makearray(len(C2);len(C2);lambda(x;y;mid(C2;x;1)&mid(C2;y;1))); textjoin("*";1;map(a;lambda(x;if(sum(map(arrayformula(mid(C2;sequence(len(C2));1));lambda(y;--isnumber(find(y;x)))))>0;x;"")))) )

In C10:

=let(a;makearray(len(C9);len(C9);lambda(x;y;mid(C9;x;1)&mid(C9;y;1))); textjoin("*";1;map(a;lambda(x;if(sum(map(arrayformula(mid(C9;sequence(len(C9));1));lambda(y;--isnumber(find(y;x)))))>0;x;"")))) )

https://docs.google.com/spreadsheets...#gid=956302076

I did it for you in your GoogleSheet - you diodn't have to do anything!!!

Glad to have helped.

If that takes care of your original question, please choose Thread Tools from the menu link above and mark this thread as SOLVED. You can also access the SOLVED tag by editing the opening post and choosing SOLVED from the drop-down to the left of the title box.

Also, if you have not already done so, remember that you can reward anyone who offered you help towards a solution for your issue by clicking the small star icon (* Add Reputation) located in the lower left corner of the post in which the help was given. By doing so you can add to the reputation(s) of each of those who offered help.