Wolstenholme numbers: Difference between revisions

=={{header|Julia}}==

{{trans|Python}}

<syntaxhighlight lang="julia">using Primes

""" Get N numbers in the series of Wolstenholme numbers """

wolstenholme(N) = map(numerator, accumulate(+, (1 // (i*i) for i in big"1":N)))

""" Abbreviate a large string by showing beginning / end and number of chars """

function abbreviate(s, term = "digits", thresh = 50, idx = thresh ÷ 2 - 3)

w = length(s)

return w < thresh ? s : s[begin:begin+idx] * ".." * s[end-idx:end] * " ($w $term)"

end

""" Run the tasks at rosettacode.org/wiki/Wolstenholme_numbers """

function process_wolstenholmes(nmax = 10000, filterto = 2000)

wols = wolstenholme(nmax)

println("Wolstenholme numbers 1:20, 500, 1000, 2500, 5000, 10000:")

for i in [1:20; [500, 1000, 2500, 5000, 10000]]

println(rpad(i, 5), ": ", abbreviate(string(wols[i])))

end

println("\nFifteen Wolstenholme primes:")

for (i, n) in enumerate(filter(isprime, @view wols[begin:filterto]))

println(rpad(i, 2), ": ", abbreviate(string(n)))

end

end

process_wolstenholmes()

</syntaxhighlight>{{out}}

<pre>

Wolstenholme numbers 1:20, 500, 1000, 2500, 5000, 10000:

1 : 1

2 : 5

3 : 49

4 : 205

5 : 5269

6 : 5369

7 : 266681

8 : 1077749

9 : 9778141

10 : 1968329

11 : 239437889

12 : 240505109

13 : 40799043101

14 : 40931552621

15 : 205234915681

16 : 822968714749

17 : 238357395880861

18 : 238820721143261

19 : 86364397717734821

20 : 17299975731542641

500 : 40989667509417020364501..12248084984597965892703 (434 digits)

1000 : 83545938483149689478187..58699094240207812766449 (866 digits)

2500 : 64537911900230612090849..91212785535902976933153 (2164 digits)

5000 : 34472086597488537716198..20022525144829082590451 (4340 digits)

10000: 54714423173933343999582..37149175649667700005717 (8693 digits)

Fifteen Wolstenholme primes:

1 : 5

2 : 266681

3 : 40799043101

4 : 86364397717734821

5 : 36190908596780862323291..68379995976006474252029 (104 digits)

6 : 33427988094524601237303..12048446489305085140033 (156 digits)

7 : 22812704758392002353774..54384405125167217413149 (218 digits)

8 : 28347687473208792918550..41045794572911130248059 (318 digits)

9 : 78440559440644426017290..55630422337523878698419 (520 digits)

10: 22706893975121925531372..03702173859396183964989 (649 digits)

11: 27310394808585898968805..03886311385662644388271 (935 digits)

12: 13001072736642048751114..78008635832246554146071 (984 digits)

13: 15086863305391456002934..94405367804007944918693 (1202 digits)

14: 23541935187269979100228..81502324742766220468879 (1518 digits)

15: 40306783143871607599250..98658901192511859288941 (1539 digits)

</pre>