random-prime ( numbits -- p ) (original) (raw)
random-prime ( numbits -- p )
Prime numbers
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Inputs
| numbits | an integer |
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Outputs
| p | an integer |
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Word description
Returns a prime number exactly numbits bits in length, with the topmost bit set to one.
Definition
: random-prime ( numbits -- p )
[ ] [ 2^ ] [ random-bits-exact next-prime ] tri 2dup <
[ 2drop random-prime ] [ 2nip ] if ;