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So what is 03dcaaaaea9e3b34b36c5e029abaf3028b39124ba8b90b0b7480256e10630052f2 then? It is 241.5.
241.5 + 241.5 = 483
So, where do we find 241.5?
https://privatekeys.pw/key/7fffffffffffffffffffffffffffffff5d576e7357a4501ddfe92f46681b1e5fHow did I find it? key middle range minus half of our privatekey: 0x7fffffffffffffffffffffffffffffff5d576e7357a4501ddfe92f46681b20a0 - 0x241 => tada
So from complexity of 11 bits, i just needed to check 10 bits now.
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i m little bit confused can you please provide me some example
241.5 would represent the floating-point equivalent of the even private key (in this example), and 241 would represent the odd public key (note: no decimal point in the even number).
There is an assumption in the excerpt that I quoted in a.a's post, that the parity of the last bit of the PK is already known - and it's only known here because the key has already been found.
But for unsolved pubkeys, the last bit is obviously unknown, so it is impossible to know whether to subtract by 0x241 [even] or 0x241 + (1*2^(-1===n-1)) [odd].