t = Integer(gets)
while t > 0
a4 = []
a7 = []
n = Integer(gets)
i = 1
while i <= n
a4 << i.to_s.count("4")
a7 << i.to_s.count("7")
i = i + 1
end
count = 0
i = 1
while ( i<=n)
if a4[i-1] == a7[i-1]
count = count + 1
else
break
end
i =i + 1
end
count = count*(count+1)/2
print "#{count}\n"
t = t - 1
end
puts a4
dCA9IEludGVnZXIoZ2V0cykKd2hpbGUgdCA+IDAKYTQgPSBbXQphNyA9IFtdCm4gPSBJbnRlZ2VyKGdldHMpCmkgPSAxCgp3aGlsZSBpIDw9IG4gCmE0IDw8IGkudG9fcy5jb3VudCgiNCIpCmE3IDw8IGkudG9fcy5jb3VudCgiNyIpCgppID0gaSArIDEKZW5kCmNvdW50ID0gMCAKaSA9IDEKd2hpbGUgKCBpPD1uKQppZiBhNFtpLTFdID09IGE3W2ktMV0KY291bnQgPSBjb3VudCArIDEKZWxzZQpicmVhawplbmQKCmkgPWkgKyAxCmVuZApjb3VudCA9IGNvdW50Kihjb3VudCsxKS8yCnByaW50ICIje2NvdW50fVxuIiAKdCA9IHQgLSAxCmVuZApwdXRzIGE0