Quad-power prime seeds: Difference between revisions

=={{header|Go}}==

{{trans|Wren}}

{{libheader|GMP(Go wrapper)}}

{{libheader|Go-rcu}}

<syntaxhighlight lang="go">package main

import (

"fmt"

big "github.com/ncw/gmp"

"rcu"

)

var p, p2 *big.Int

func isQuadPowerPrimeSeed(n uint64) bool {

nn := new(big.Int).SetUint64(n)

p.Set(nn)

k := new(big.Int).SetUint64(n + 1)

p2.Add(p, k)

if !p2.ProbablyPrime(15) {

return false

}

for i := 0; i < 3; i++ {

p.Mul(p, nn)

p2.Set(p)

p2.Add(p2, k)

if !p2.ProbablyPrime(15) {

return false

}

}

return true

}

func ord(c int) string {

m := c % 100

if m > 4 && m <= 20 {

return "th"

}

m %= 10

switch m {

case 1:

return "st"

case 2:

return "nd"

case 3:

return "rd"

default:

return "th"

}

}

func main() {

p = new(big.Int)

p2 = new(big.Int)

c := 0

m := 1

n := uint64(1)

fmt.Println("First fifty quad-power prime seeds:")

for ; c < 50; n++ {

if isQuadPowerPrimeSeed(n) {

fmt.Printf("%7s ", rcu.Commatize(int(n)))

c++

if c%10 == 0 {

fmt.Println()

}

}

}

fmt.Println("\nFirst quad-power prime seed greater than:")

for {

if isQuadPowerPrimeSeed(n) {

c++

if n > 1000000*uint64(m) {

ns := rcu.Commatize(int(n))

fmt.Printf(" %2d million is the %d%s: %10s\n", m, c, ord(c), ns)

m++

if m == 11 {

break

}

}

}

n++

}

}</syntaxhighlight>

{{out}}

<pre>

First fifty quad-power prime seeds:

1 2 5 6 69 131 426 1,665 2,129 2,696

5,250 7,929 9,689 13,545 14,154 14,286 16,434 19,760 25,739 27,809

29,631 36,821 41,819 46,619 48,321 59,030 60,500 61,955 62,321 73,610

77,685 79,646 80,535 82,655 85,251 86,996 91,014 96,566 97,739 105,939

108,240 108,681 119,754 122,436 123,164 126,489 140,636 150,480 153,179 163,070

First quad-power prime seed greater than:

1 million is the 141st: 1,009,286

2 million is the 234th: 2,015,496

3 million is the 319th: 3,005,316

4 million is the 383rd: 4,004,726

5 million is the 452nd: 5,023,880

6 million is the 514th: 6,000,554

7 million is the 567th: 7,047,129

8 million is the 601st: 8,005,710

9 million is the 645th: 9,055,151

10 million is the 701st: 10,023,600

</pre>