Sylvester's sequence: Difference between revisions
→{{header|jq}}
Line 335:
sylvester = iterate (\x -> x * (x-1) + 1) 2</lang>
=={{header|jq}}==
<lang jq># Generate the sylvester integers:
def sylvester:
foreach range(0; infinite) as $i ({prev: 1, product: 1};
.product *= .prev
| .prev = .product + 1;
.prev);</lang>
Left padding:
<lang jq>
def lpad($len; $fill): tostring | ($len - length) as $l | ($fill * $l)[:$l] + .;
def lpad($len): lpad($len; " ");
def lpad: lpad(4);</lang>
The task:
<lang jq>[limit(10; sylvester)]
| "First 10 Sylvester numbers:",
(range(0;10) as $i | "\($i+1|lpad) => \(.[$i])"),
"",
"Sum of reciprocals of first 10 is approximately: \(map( 1/ .) | add)"
</lang>
{{out}}
For integer precision, we will use `gojq`, the "go" implementation of jq.
<pre>First 10 Sylvester numbers:
1 => 2
2 => 3
3 => 7
4 => 43
5 => 1807
6 => 3263443
7 => 10650056950807
8 => 113423713055421844361000443
9 => 12864938683278671740537145998360961546653259485195807
10 => 165506647324519964198468195444439180017513152706377497841851388766535868639572406808911988131737645185443
Sum of reciprocals of first 10 is approximately: 0.9999999999999999</pre>
=={{header|Julia}}==
<lang julia>sylvester(n) = (n == 1) ? big"2" : prod(sylvester, 1:n-1) + big"1"
| |||