which number best completes the sequence 1 1 3 2 4 6 5 25

[mikebw]

[quote Carm]
Second
2+4=6-2=3+5=8-2=6+6=12-2=10
+x , -2, +(x+1), -2, +(x+2), -2,+(x+3), -2

x=4
Pretty sure that 6-2 =4.