Wagstaff primes: Difference between revisions
python
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10: 43: 2932031007403
</pre>
=={{header|Python}}==
<syntaxhighlight lang="python">""" Rosetta code Wagstaff_primes task """
from sympy import isprime
def wagstaff(N):
""" find first N Wagstaff primes """
pri, wcount = 2, 0
while wcount < N:
pri +=1
if isprime(pri):
wag = (2**pri + 1) // 3
if isprime(wag):
wcount += 1
print(f'{wcount: 2}: {pri: 5} => ',
f'{wag:,}' if wcount < 11 else f'[{len(str(wag))} digit number]')
wagstaff(22)
</syntaxhighlight>{{out}}
<pre>
1: 3 => 3
2: 5 => 11
3: 7 => 43
4: 11 => 683
5: 13 => 2,731
6: 17 => 43,691
7: 19 => 174,763
8: 23 => 2,796,203
9: 31 => 715,827,883
10: 43 => 2,932,031,007,403
11: 61 => [18 digit number]
12: 79 => [24 digit number]
13: 101 => [30 digit number]
14: 127 => [38 digit number]
15: 167 => [50 digit number]
16: 191 => [58 digit number]
17: 199 => [60 digit number]
18: 313 => [94 digit number]
19: 347 => [104 digit number]
20: 701 => [211 digit number]
21: 1709 => [514 digit number]
22: 2617 => [788 digit number]
</pre>
=={{header|Raku}}==
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