Simple maths problem.
an is defined as 1 + (1/n).
Sn is defined as a1 + a2 + ... + an.
So we're gonna calculate S15, and we're gonna use object-oriented programming because I'm me.
use v5.16;
package Local::App {
use Zydeco;
use List::Util 'sum';
class Calc {
method a ( PositiveInt $n ) = 1 + (1/$n);
method S ( PositiveInt $n ) = sum( map $self->a($_), 1 .. $n )
+;
}
}
my $calc = Local::App->new_calc;
say $calc->S(15);
Or, using rational numbers:
use v5.16;
package Local::App {
use Zydeco;
use List::Util 'sum';
class Calc {
method r ( $n ) = 1/$n;
method a ( PositiveInt $n ) = 1 + $self->r($n);
method S ( PositiveInt $n ) = sum( map $self->a($_), 1 .. $n )
+;
class +Rational {
use Math::BigRat;
method r ( $n ) = Math::BigRat->new("1/$n");
}
}
}
my $calc = Local::App->new_calc_rational;
say $calc->S(15);