Question

Hi, i have 8 byte series for 1,2,3,4,5,6,...sequentially. and i want to know the function(formula) for solving these series that a particular number i can find from a particular series.
my series is:-

8 byte series finding value
20 95 4a a5 52 a9 18 c0 = 1,
a0 54 2a 95 4a a5 0a c0 = 2,
00 f8 fb fd 7e bf df bf = 3,
c0 56 ab d5 6a b5 02 40 = 4,
00 16 8b c5 62 b1 14 40 = 5

so, what should be the function(formula) for these series . that i can apply all the series and i can find the number according to that series.