local int = require "int"
local fmt = require "fmt"

local limit <const> = 1e10
local primes = int.primes(limit, true)
local orm25 = {}
local j = limit / 10
local count = 0
local counts = {}
for i = 1, #primes - 2 do
    local p1 = primes[i]
    local p2 = primes[i + 1]
    local p3 = primes[i + 2]
    if (p2 - p1) % 18 != 0 or (p3 - p2) % 18 != 0 then continue end
    local key1 = 1
    for int.digits(p1) as dig do key1 *= primes[dig + 1] end
    local key2 = 1
    for int.digits(p2) as dig do key2 *= primes[dig + 1] end
    if key1 != key2 then continue end
    local key3 = 1
    for int.digits(p3) as dig do key3 *= primes[dig + 1] end
    if key2 == key3 then
        if count < 25 then orm25:insert(p1) end
        if p1 >= j then
            counts:insert(count)
            j *= 10
        end
        count += 1
    end
end
counts:insert(count)
print("Smallest members of first 25 Ormiston triples:")
fmt.tprint("%10s ", orm25:mapped(|e| -> fmt.int(e)), 5)
print()
j = limit / 10
for i = 1, #counts do
    fmt.print("%s Ormiston triples before %s",  fmt.int(counts[i]), fmt.int(j))
    j *= 10
end