阶梯状排列 (10661)

E2 右拉 下拉{=IF(COUNTIF($1:1,"@")+COUNTIF($D2:D2,"@")>=$B$2,"",IF(OR((ROW($1:$19)>=COLUMN($A:$T))*(ROW($1:$19)/1%+COLUMN($A:$T))=ROW(A1)/1%+COLUMN(A1)),"@",""))

另解=IF(COUNTIF($1:1,"@")+COLUMN(A1)>$B$2,"",IF(ROW(A1)>=COLUMN(A1),"@",""))