Searching for ids that didn't get a blast hit

cat output_file.txt | cut -f 1 | uniq | wc -l

 1047  cat output_file.txt | csvtk cut -f 1
 1048  cat output_file.txt | csvtk cut -c 1
 1049  cat output_file.txt | csvtk cut -f 1
 1050  csvtk cut -h
 1051  cat output_file.txt | csvtk cut -f 1
 1052  cat output_file.txt | csvtk cut -f 2
 1053  cat output_file.txt 
 1054  cat output_file.txt | less -S
 1055  cat output_file.txt | column -t | less -S
 1056  csvtk cut -h
 1057  csvtk cut -f colA output_file.txt 
 1058  cat output_file.txt | awk '{print $1}'
 1059  cat output_file.txt | awk '{FS="\t; "print $0}'
 1060  cat output_file.txt | awk '{FS="\t"; print $0}'
 1061  cat output_file.txt | awk '{OFS="\t"; print $0}'
 1062  cat output_file.txt | awk '{OFS="\t"; print $0}' | csvtk cut -f 1
 1063  cat output_file.txt | awk '{OFS="\t"; print $1}' | uniq | wc -l
 1064  ls
 1065  cat output_file_filtered.tsv | csvtk cut -f 1
 1066  cat output_file_filtered.tsv | awk '{print $1}'
 1067  cat output_file_filtered.tsv | awk '{print $1}' > file1.txt
 1068  cat file1.txt 
 1069  cat output_file.txt | awk '{print $1}' > file2.txt
 1070  diff file1.txt file2.txt 
 1071  diff file1.txt file2.txt | grep '>'
 1072  diff file1.txt file2.txt | grep '>' | grep -v '>'
 1073  diff file1.txt file2.txt | grep '>' | wc -l
 
 
# IDs_filtered_no_NAs.txt is the first column (qseqids) of the filtered blast output (filtered by taking only the hit with the highest bitsore per sample)
# qseqid_list_big.txt is the first column of the ordered DEG data table (prior to blasting and filtering)
diff IDs_filtered_no_NAs.txt qseqid_list_big.txt | grep '>' | awk '{print $2}' > file3.txt