Sequence of primorial primes: Difference between revisions

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 {{out}}
 <pre>   1,   2,   3,   4,   5,   6,  11,  13,  24,  66,  68,  75, 167, 171, 172, 287, 310, 352, 384, 457,</pre>
+=={{header|Go}}==
+<lang go>package main
+import (
+    "fmt"
+    "math/big"
+)
+func main() {
+    one := big.NewInt(1)
+    pm := big.NewInt(1) // primorial
+    var px, nx int
+    var pb big.Int // a scratch value
+    primes(4000, func(p int64) bool {
+        pm.Mul(pm, pb.SetInt64(p))
+        px++
+        if pb.Add(pm, one).ProbablyPrime(0) ||
+            pb.Sub(pm, one).ProbablyPrime(0) {
+            fmt.Print(px, " ")
+            nx++
+            if nx == 20 {
+                fmt.Println()
+                return false
+            }
+        }
+        return true
+    })
+}
+// Code taken from task Sieve of Eratosthenes, and put into this function
+// that calls callback function f for each prime < limit, but terminating
+// if the callback returns false.
+func primes(limit int, f func(int64) bool) {
+    c := make([]bool, limit)
+    c[0] = true
+    c[1] = true
+    lm := int64(limit)
+    p := int64(2)
+    for {
+        f(p)
+        p2 := p * p
+        if p2 >= lm {
+            break
+        }
+        for i := p2; i < lm; i += p {
+            c[i] = true
+        }
+        for {
+            p++
+            if !c[p] {
+                break
+            }
+        }
+    }
+    for p++; p < lm; p++ {
+        if !c[p] && !f(p) {
+            break
+        }
+    }
+}</lang>
+{{out}}
+<pre>
+2 3 4 5 6 11 13 24 66 68 75 167 171 172 287 310 352 384 457
+</pre>
 =={{header|Haskell}}==