Erdős-primes: Difference between revisions
added AWK
m (→{{header|Factor}}: lnth is a thing. I just learned this a few weeks ago...) |
Catskill549 (talk | contribs) (added AWK) |
||
Line 16:
<br><br>
=={{header|AWK}}==
<lang AWK>
# syntax: GAWK -f ERDOS-PRIMES.AWK
# converted from FreeBASIC
BEGIN {
while (++i) {
if (is_erdos_prime(i)) {
if (i < 2500) {
printf("%d ",i)
count1++
}
if (++count2 == 7875) {
printf("\nErdos primes 1-2500: %d\nErdos prime %d: %d\n",count1,count2,i)
break
}
}
}
exit(0)
}
function is_erdos_prime(p, kf,m) {
if (!is_prime(p)) { return(0) }
kf = m = 1
while (kf < p) {
kf *= m++
if (is_prime(p-kf)) { return(0) }
}
return(1)
}
function is_prime(x, i) {
if (x <= 1) {
return(0)
}
for (i=2; i<=int(sqrt(x)); i++) {
if (x % i == 0) {
return(0)
}
}
return(1)
}
</lang>
{{out}}
<pre>
2 101 211 367 409 419 461 557 673 709 769 937 967 1009 1201 1259 1709 1831 1889 2141 2221 2309 2351 2411 2437
Erdos primes 1-2500: 25
Erdos prime 7875: 999721
</pre>
=={{header|C++}}==
{{libheader|Primesieve}}
| |||