Pseudo-quine polyglot language-detection counters
Python 2, Python 3, >&lt;> (Fish)

#;n0
import sys
x='\\\'\nn#;n0import sysx=v=int(1/2*2)sys.stdout.write(x[4:7]),sys.stdout.write(chr(43)+str(v)+chr(42)+chr(50)),sys.stdout.write(x[851:-1]),sys.stdout.write(x[7:8]),sys.stdout.write(x[2:3]),sys.stdout.write(x[8:18]),sys.stdout.write(x[2:3]),sys.stdout.write(x[18:20]),sys.stdout.write(x[1:2]),sys.stdout.write(x[0:1]),sys.stdout.write(x[0:1]),sys.stdout.write(x[0:1]),sys.stdout.write(x[1:2]),sys.stdout.write(x[0:1]),sys.stdout.write(x[3:4]),sys.stdout.write(x[3:4]),sys.stdout.write(x[4:7]),sys.stdout.write(x[7:8]),sys.stdout.write(x[8:18]),sys.stdout.write(x[18:20]),sys.stdout.write(x[20:32]),sys.stdout.write(x[32:851]),sys.stdout.write(chr(43)+str(v)+chr(42)+chr(50)),sys.stdout.write(x[851:-1]),sys.stdout.write(x[3:4]),sys.stdout.write(x[1:2]),sys.stdout.write(x[2:3]),sys.stdout.write(x[20:32]),sys.stdout.write(x[2:3]),sys.stdout.write(x[32:851])n'
v=int(1/2*2)
sys.stdout.write(x[4:7]),sys.stdout.write(chr(43)+str(v)+chr(42)+chr(50)),sys.stdout.write(x[851:-1]),sys.stdout.write(x[7:8]),sys.stdout.write(x[2:3]),sys.stdout.write(x[8:18]),sys.stdout.write(x[2:3]),sys.stdout.write(x[18:20]),sys.stdout.write(x[1:2]),sys.stdout.write(x[0:1]),sys.stdout.write(x[0:1]),sys.stdout.write(x[0:1]),sys.stdout.write(x[1:2]),sys.stdout.write(x[0:1]),sys.stdout.write(x[3:4]),sys.stdout.write(x[3:4]),sys.stdout.write(x[4:7]),sys.stdout.write(x[7:8]),sys.stdout.write(x[8:18]),sys.stdout.write(x[18:20]),sys.stdout.write(x[20:32]),sys.stdout.write(x[32:851]),sys.stdout.write(chr(43)+str(v)+chr(42)+chr(50)),sys.stdout.write(x[851:-1]),sys.stdout.write(x[3:4]),sys.stdout.write(x[1:2]),sys.stdout.write(x[2:3]),sys.stdout.write(x[20:32]),sys.stdout.write(x[2:3]),sys.stdout.write(x[32:851])


Python explanation

The Python 2 and Python 3 interpreters work similarly except the v=int(1/2*2) variable gets different values (0 and 1) as Python 2 uses float division and Python 3 uses integer division.

In every run they add the expression +0*2 or +1*2  to the first line (after #;n) and to the x string (after the last write command). The >&lt;> interpreter uses the first addition and the Pythons use the second one to create correct quines.

Code after B(A(B(B(x)))):

#;n+1*2+0*2+1*2+1*20
import sys
x='\\\'\nn#;n0import sysx=v=int(1/2*2)sys.stdout.write(x[4:7]),sys.stdout.write(chr(43)+str(v)+chr(42)+chr(50)),sys.stdout.write(x[851:-1]),sys.stdout.write(x[7:8]),sys.stdout.write(x[2:3]),sys.stdout.write(x[8:18]),sys.stdout.write(x[2:3]),sys.stdout.write(x[18:20]),sys.stdout.write(x[1:2]),sys.stdout.write(x[0:1]),sys.stdout.write(x[0:1]),sys.stdout.write(x[0:1]),sys.stdout.write(x[1:2]),sys.stdout.write(x[0:1]),sys.stdout.write(x[3:4]),sys.stdout.write(x[3:4]),sys.stdout.write(x[4:7]),sys.stdout.write(x[7:8]),sys.stdout.write(x[8:18]),sys.stdout.write(x[18:20]),sys.stdout.write(x[20:32]),sys.stdout.write(x[32:851]),sys.stdout.write(chr(43)+str(v)+chr(42)+chr(50)),sys.stdout.write(x[851:-1]),sys.stdout.write(x[3:4]),sys.stdout.write(x[1:2]),sys.stdout.write(x[2:3]),sys.stdout.write(x[20:32]),sys.stdout.write(x[2:3]),sys.stdout.write(x[32:851])+1*2+0*2+1*2+1*2n'
v=int(1/2*2)
sys.stdout.write(x[4:7]),sys.stdout.write(chr(43)+str(v)+chr(42)+chr(50)),sys.stdout.write(x[851:-1]),sys.stdout.write(x[7:8]),sys.stdout.write(x[2:3]),sys.stdout.write(x[8:18]),sys.stdout.write(x[2:3]),sys.stdout.write(x[18:20]),sys.stdout.write(x[1:2]),sys.stdout.write(x[0:1]),sys.stdout.write(x[0:1]),sys.stdout.write(x[0:1]),sys.stdout.write(x[1:2]),sys.stdout.write(x[0:1]),sys.stdout.write(x[3:4]),sys.stdout.write(x[3:4]),sys.stdout.write(x[4:7]),sys.stdout.write(x[7:8]),sys.stdout.write(x[8:18]),sys.stdout.write(x[18:20]),sys.stdout.write(x[20:32]),sys.stdout.write(x[32:851]),sys.stdout.write(chr(43)+str(v)+chr(42)+chr(50)),sys.stdout.write(x[851:-1]),sys.stdout.write(x[3:4]),sys.stdout.write(x[1:2]),sys.stdout.write(x[2:3]),sys.stdout.write(x[20:32]),sys.stdout.write(x[2:3]),sys.stdout.write(x[32:851])


>&lt;> (Fish) explanation

When you run the >&lt;> interpreter the code pointer bounces back from the # wraps around the first line and starting from the end of the first line and heading West starts pushing numbers onto the stack. If an operator comes (+ or *) it pops the top two elements from the stack and pushes back the result. With this method we end up with the base2 representation of the previous runs (13 in the former example). This is the desired number so we output it with n and terminate with ;.