31 lines
894 B
Text
31 lines
894 B
Text
import "./math" for Int
|
|
import "./fmt" for Fmt
|
|
|
|
var limit = 1e9
|
|
var gapStarts = {}
|
|
var primes = Int.segmentedSieve(limit * 5, 128 * 1024) // 128 KB cache
|
|
for (i in 1...primes.count) {
|
|
var gap = primes[i] - primes[i-1]
|
|
if (!gapStarts[gap]) gapStarts[gap] = primes[i-1]
|
|
}
|
|
var pm = 10
|
|
var gap1 = 2
|
|
while (true) {
|
|
while (!gapStarts[gap1]) gap1 = gap1 + 2
|
|
var start1 = gapStarts[gap1]
|
|
var gap2 = gap1 + 2
|
|
if (!gapStarts[gap2]) {
|
|
gap1 = gap2 + 2
|
|
continue
|
|
}
|
|
var start2 = gapStarts[gap2]
|
|
var diff = (start2 - start1).abs
|
|
if (diff > pm) {
|
|
Fmt.print("Earliest difference > $,d between adjacent prime gap starting primes:", pm)
|
|
Fmt.print("Gap $d starts at $,d, gap $d starts at $,d, difference is $,d.\n", gap1, start1, gap2, start2, diff)
|
|
if (pm == limit) break
|
|
pm = pm * 10
|
|
} else {
|
|
gap1 = gap2
|
|
}
|
|
}
|