but you just have to create $x in a slightly different way

No you don't. The direct equivalent works just fine. 

>perl -MMath::BigInt -le"my $x = Math::BigInt->new(2) ** Math::BigInt-
+>new(1024); print $x"
1797693134862315907729305190789024733617976978942306572734300811577326
+758055009631327084773224075360211201138798713933576587897688144166224
+928474306394741243777678934248654852763022196012460941194530829520850
+057688381506823424628814739131105408272371633505106845862982399472459
+38479716304835356329624224137216

[download]

It can even be simplified 

>perl -MMath::BigInt -le"my $x = Math::BigInt->new(2) ** 1024; print $
+x"
1797693134862315907729305190789024733617976978942306572734300811577326
+758055009631327084773224075360211201138798713933576587897688144166224
+928474306394741243777678934248654852763022196012460941194530829520850
+057688381506823424628814739131105408272371633505106845862982399472459
+38479716304835356329624224137216

[download]

In reply to Re^2: big integers forcing me to be a C programmer: "range iterator outside integer range" by ikegami
in thread big integers forcing me to be a C programmer: "range iterator outside integer range" by Boldra

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