count last n times TRUE in column, skip is not TRUE or FALSE

[frederik00]

Hello everyone, nice to meet all of you!

I tried figuring this out but I couldn't find anything online.

Last 5 times TRUE, skip anything that's not TRUE or FALSE. See my example

I like to change the number a lot so if it's possible for it to be dynamic so I can change the 5 to something else, it would be awesome!

 

[hagia_sofia]

Here is an attempt:

=LET(
array,--(TOCOL(A1:B9)),
nth,C2,
count,SUM(array),
seq,WRAPROWS(SCAN(count+1,array,LAMBDA(a,b,IF(b=0,a,a-1)))*array,2),
a,IFERROR(ROWS(FILTER(CHOOSECOLS(seq,1),(CHOOSECOLS(seq,1)>0)*(CHOOSECOLS(seq,1)<=nth))),0),
b,IFERROR(ROWS(FILTER(CHOOSECOLS(seq,2),(CHOOSECOLS(seq,2)>0)*(CHOOSECOLS(seq,2)<=nth))),0),
HSTACK(a,b))

where "C2" represents the cell where there is the value of last N.

 

[Scott Huish]

How about:

Book1
	A	B	C
1	TRUE	FALSE
2	TRUE		5
3	TRUE	FALSE
4	FALSE	TRUE
5	FALSE	TRUE
6	FALSE
7	TRUE	TRUE
8	FALSE	FALSE
9	TRUE
10
11	2	3
Sheet1

Cell Formulas
Range	Formula
A11:B11	A11	=SUM(--LET(a,FILTER(A1:A9,A1:A9<>""),DROP(a,COUNTA(a)-$C$2)))