64 lines
1,015 B
Text
64 lines
1,015 B
Text
.TH FACTOR 1
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.CT 1 numbers
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.SH NAME
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factor, primes \- factor a number, generate large primes
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.SH SYNOPSIS
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.B factor
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[
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.I number
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]
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.PP
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.B primes
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.I start
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[
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.I finish
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]
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.SH DESCRIPTION
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.I Factor
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prints
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.I number
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and its prime factors,
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each repeated the proper number of times.
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The number must be positive and less than
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.if n 2**54
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.if t 2\u\s754\s0\d
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(about
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.if n 1.8e16)
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.if t 1.8\(mu10\u\s716\s0\d\|).
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.PP
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If no
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.I number
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is given,
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.I factor
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reads a stream of numbers from the standard input and factors them.
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It exits on any input not a positive integer.
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Maximum running time is proportional to
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.if n sqrt(n).
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.if t .I \(sr\o'n\(rn'\f1.
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.PP
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.PP
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.I Primes
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prints the prime numbers ranging from
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.I start
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to
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.IR finish ,
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where
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.I start
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and
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.I finish
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are positive numbers less than
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.if n 2**56.
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.if t 2\u\s756\s0\d.
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If
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.I finish
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is missing,
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.I primes
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prints without end;
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if
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.I start
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is missing, it reads the starting number from the
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standard input.
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.SH SOURCE
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.B /sys/src/cmd/factor.c
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.br
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.B /sys/src/cmd/primes.c
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