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Super-Poulet numbers: Difference between revisions

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Super-Poulet numbers (view source)

Revision as of 00:00, 17 August 2022

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Meh, fix case errors
m (Thundergnat moved page Super-Poulet number to Super-Poulet numbers: Should be plural)
m (Meh, fix case errors)
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{{draft task}}
 
A [[wp:Super-Poulet_number|Supersuper-Poulet number]] is a [[wp:Fermat_pseudoprime|Poulet number]] (or Fermat pseudoprime to base 2) whose every divisor '''''d''''' evenly divides '''''2<sup>d</sup> − 2'''''.
 
 
;Task
* Find and display the first '''20''' Supersuper-Poulet numbers.
 
 
;Stretch
* Find and display the index and value of the first Supersuper-Poulet number greater than one million.
 
 
;See also
;*[[Fermat pseudoprimes|Task: Fermat pseudoprimes]]
;*[[wp:Super-Poulet_number|Wikipedia: Supersuper-Poulet number]]
;*[[oeis:A050217|OEIS:A050217 - Supersuper-Poulet numbers]]
 
 
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my @super-poulet = @poulet.grep: { all .&divisors.skip(1).map: { 2 == expmod 2, $_, $_ } }
 
say "First 20 Supersuper-Poulet numbers:\n" ~ @super-poulet[^20].gist;
 
for 1e6.Int, 1e7.Int -> $threshold {
say "\nIndex and value of first Supersuper-Poulet greater than {$threshold.&cardinal}:";
my $index = @super-poulet.first: * > $threshold, :k;
say "{(1+$index).&ordinal-digit} Supersuper-Poulet number == " ~ @super-poulet[$index].&comma;
}</lang>
{{out}}
<pre>First 20 Supersuper-Poulet numbers:
(341 1387 2047 2701 3277 4033 4369 4681 5461 7957 8321 10261 13747 14491 15709 18721 19951 23377 31417 31609)
 
Index and value of first Supersuper-Poulet greater than one million:
109th Supersuper-Poulet number == 1,016,801
 
Index and value of first Supersuper-Poulet greater than ten million:
317th Supersuper-Poulet number == 10,031,653
</pre>
Thundergnat
10,327

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