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SHA-256 initial values

The simple workout to arrive at the initial values for sha-256

The first 32 bit of the fractional part of the sqroot (first 8 prime number 2-19)

Alright what does it say 

Sqrroot(prime)-

Let’s say the first prime is 2

Sqroot(2)  = 1.414213562373095

Convert to hexadecimal-

Since we are worried about the fractional part alone

Converting the fractional part would be easy

Fractional part-

0.414213562373095

Multiply the fractional part with 16 to arrive at hex

0.414213562373095*16= 6.62741699796952

0.62741699796952*16= 10.03867196751232

0.03867196751232*16=0.61875148019712

0.61875148019712*16=9.90002368315392

0.90002368315392*16=14.40037893046272

0.40037893046272*16=6.40606288740352

0.40606288740352*16=6.49700619845632

0.49700619845632*16=7.95209917530112


Resulting hexadecimal would be 6a09e667 which is 

h0 := 0x6a09e667

Iam going to stop at the 8th iteration , why is that ?

Since we are interested in 32 bit (8*4=32)

Alright to make it clear 

Convert hexadecimal- binary arriving at 32 bits

Please have a look at the hex - bin table

6a09e667- 0110 1010 0000 1001 1110 0110 0110 0111

Enjoy hashing.




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