diff --git a/Manticore/Num/ContinuedFraction.pm b/Manticore/Num/ContinuedFraction.pm
index 5f6f039..f6dde0b 100644
--- a/Manticore/Num/ContinuedFraction.pm
+++ b/Manticore/Num/ContinuedFraction.pm
@@ -32,10 +32,30 @@ sub child {
   my $self = shift;
   if(not $self->{c}) {
     my ($a, $r) = @{$self}{qw(a r)};
+    if(0 == $r) {
+      return undef
+    }
     my $c = Manticore::Num::ContinuedFraction->new(1/$r);
     $self->{c} = $c;
   }
   return $self->{c}
 }
 
+sub firstk {
+  my ($self, $k) = @_;
+  if($k <= 0) {
+    return []
+  } else {
+    my $c = $self->child();
+    return [$self->{a}] unless defined $c;
+    my $l = $c->firstk($k-1);
+    unshift @$l, $self->{a};
+    return $l
+  }
+}
+
+
+
+
+
 1;
diff --git a/Manticore/Num/Trig.pm b/Manticore/Num/Trig.pm
new file mode 100644
index 0000000..1135f00
--- /dev/null
+++ b/Manticore/Num/Trig.pm
@@ -0,0 +1,34 @@
+package Manticore::Num::Trig;
+
+use strict;
+use warnings;
+
+# 1/0! - x^2/2! + x^4/4! - x^6/6!
+sub proxCos {
+  my ($steps, $x) = @_;
+  my $mxsq = -$x*$x;
+  my $sum = 0;
+  my $fa = 1;
+  for(1..$steps) {
+    my $step2 = $_ * 2;
+    $sum += $fa;
+    $fa *= $mxsq/($step2*($step2-1))
+  }
+  return $sum
+}
+
+# x/1! - x^3/3! + x^5/5! - x^7/7!
+sub proxSin {
+  my ($steps, $x) = @_;
+  my $mxsq = -$x*$x;
+  my $sum = 0;
+  my $fa = $x;
+  for(1..$steps) {
+    my $step2 = $_ * 2;
+    $sum += $fa;
+    $fa *= $mxsq/($step2*($step2+1))
+  }
+  return $sum
+}
+
+1;
diff --git a/tests/testCf.pl b/tests/testCf.pl
index 97a4117..cd5e7c6 100755
--- a/tests/testCf.pl
+++ b/tests/testCf.pl
@@ -12,9 +12,13 @@ BEGIN {
 
 use Manticore::Num::ContinuedFraction;
 
-my $pi = Manticore::Num::ContinuedFraction->new(pi);
+my $pi = Manticore::Num::ContinuedFraction->new(7.25);
 
-print $pi->child();
+#print $pi->child();
+#
+#print Data::Dumper::Dumper($pi);
 
-print Data::Dumper::Dumper($pi);
+my $c = $pi->firstk(25);
+
+print "[[ @$c ]]\n";