perl and raku solutions

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diff --git a/challenge-170/steve-g-lynn/perl/ch-1.pl b/challenge-170/steve-g-lynn/perl/ch-1.pl
new file mode 100755
index 0000000000..f5ab6733eb
--- /dev/null
+++ b/challenge-170/steve-g-lynn/perl/ch-1.pl
@@ -0,0 +1,37 @@
+#!/usr/bin/perl
+
+use Math::Prime::Util::GMP qw(next_prime);
+
+for my $i (0 .. 10){
+	print &primorial($i)," ";
+}
+
+print "\n";
+
+
+sub primorial {
+	#-- old-fashioned perl using dynamic scope and typeglobs
+	local ($n) = @_;
+	
+	#-- nested private sub: recursively find the n'th prime
+	local *nth_prime = sub {
+		local ($n)=@_;
+		
+		if ($n==0){
+			return 1;
+		} else {
+			return next_prime( 
+				&nth_prime (
+					$n-1
+				) );
+		}	
+	};
+
+	#-- back to primorial sub: recursively compute primorial
+	if ($n==0){
+		return 1;
+	} else {
+		return &nth_prime($n)*&primorial($n-1);
+	}	
+}
+
diff --git a/challenge-170/steve-g-lynn/perl/ch-2.pl b/challenge-170/steve-g-lynn/perl/ch-2.pl
new file mode 100755
index 0000000000..d089884d24
--- /dev/null
+++ b/challenge-170/steve-g-lynn/perl/ch-2.pl
@@ -0,0 +1,107 @@
+#!/usr/bin/perl
+
+# Old-fashioned perl4-style approach modelling a matrix as a hash:
+# item at m'th row and n'th column of matrix M represented as $M{'m,n'}
+# (sadly the bareword form $M{m,n} is now deprecated.)
+#
+# This is a convenient representation for computing kronecker products
+# when the inputs are sparse matrices.
+
+# logic: compute the kronecker product C=kron(A,B) in an intermediate form 
+# first as a hash C{m,n} where the indices m,n are the same as those in A, 
+# and C{m,n} is a stringified list of the values in the matrix A{m,n} * B.
+
+# Then flatten C to return it as an old-fashioned hash-style matrix 
+# like A and B.
+#
+
+use List::Pairwise qw(mapp);
+
+local %A=('1,1',1,'1,2',2,'2,1',3,'2,2',4);
+local %B=('1,1',5,'1,2',6,'2,1',7,'2,2',8);
+
+local %C= &kron(*A,*B);
+
+foreach my $i (1 .. 4) {
+	foreach my $j (1 .. 4) {
+		print $C{$i.','.$j}," ";	
+	}
+	print "\n";
+}
+
+sub kron {
+	#-- old-fashioned approach using dynamic scope and typeglobs
+	
+	local (*A, *B)=@_; #--%A, %B matrices to be kroneckered
+	local (*C, *C_wip); 
+	#-- %C return value, %C_wip intermediate non-flat object
+
+	#-- nested subs for supporting calculations
+	#-- get matrix dimensions
+	local *find_mat_dims = sub {
+		local (*matrix)=@_;
+		my ($nrow, $ncol)=(0,0);
+		
+		for my $i (keys %matrix){
+			my ($row, $col)=split(/,/,$i);
+			($row > $nrow) && ($nrow = $row);
+			($col > $ncol) && ($ncol = $col);
+		}
+		return ($nrow, $ncol);
+	};
+
+	local *scalar_times_mat = sub {
+	#-- nested sub to multiply a scalar into
+	#-- every element of a matrix
+	
+		local ($scalar, *matrix)=@_;
+	
+		my %matrix_copy = %matrix;
+		mapp { $b = $scalar * $b} %matrix_copy;
+		#-- $a is key, $b is value in List::Pairwise syntax
+		
+		return %matrix_copy;
+	}; 
+
+	#-- nested sub to create C_wip
+	local *assemble_C_wip = sub {
+		for my $i (keys %A){
+			$C_wip{$i} = join(':',&scalar_times_mat( $A{$i}, *B ));
+			#-- e.g., 1,2 -> '1,2:12:2,1:14:1,1:10:2,2:16'
+		}
+		return %C_wip;
+	};
+
+	#-- nested sub to flatten C_wip
+	# e.g., 1,2 -> '1,2:12:2,1:14:1,1:10:2,2:16'
+	# flattens to ('1,4' -> 12, '2,3'->14, '1,3'->10, '2,4'->16)
+	# transform 'rowA,colA' -> '..rowB,colB..'
+	# to (rowB+(rowA-1)*nrow_B),(colB+(colA-1)*ncol_B) 
+	# which is the 'row, col' in the flattened Kronecker product
+	 	 
+	local *flatten_C_wip = sub {
+		local @C=();
+		for my $i (keys %C_wip){
+			my ($row_A, $col_A)=split(/,/,$i);
+			my ($entry)=$C_wip{$i};			
+			$entry =~ s/(\d+),(\d+)/
+				($1+($row_A-1)*$nrow_B) .','.
+				($2+($col_A-1)*$nrow_B)
+				/gex; 
+			push @C, split(/:/,$entry);
+		}
+		return @C;
+	};
+
+	#-- end nested sub definitions, back to main &kron
+	
+	local ($nrow_B, $ncol_B) = &find_mat_dims(*B);	
+	
+	&assemble_C_wip();
+	
+	%C=&flatten_C_wip();
+	
+	return  %C;
+
+}
+
diff --git a/challenge-170/steve-g-lynn/raku/ch-1.p6 b/challenge-170/steve-g-lynn/raku/ch-1.p6
new file mode 100755
index 0000000000..cde6b7282b
--- /dev/null
+++ b/challenge-170/steve-g-lynn/raku/ch-1.p6
@@ -0,0 +1,29 @@
+#!/usr/bin/raku
+
+use Inline::Perl5;
+use Math::Prime::Util::GMP:from<Perl5> <next_prime>;
+
+for (0 .. 10) -> $n {
+	print primorial($n)," ";
+}
+
+say "";
+
+sub primorial (UInt $n){
+	if ($n==0) {
+		return 1;
+	}  else {
+		return nth-prime($n) * primorial($n-1);
+	}	
+}
+
+#recursively find the n'th prime
+sub nth-prime (UInt $n) {
+	if ($n==0) {
+		return 1;
+	} else {
+	 	return next_prime( 
+			nth-prime ($n-1) );
+	}	
+}
+
diff --git a/challenge-170/steve-g-lynn/raku/ch-2.p6 b/challenge-170/steve-g-lynn/raku/ch-2.p6
new file mode 100755
index 0000000000..83ac5ba027
--- /dev/null
+++ b/challenge-170/steve-g-lynn/raku/ch-2.p6
@@ -0,0 +1,14 @@
+#!/usr/bin/raku
+
+use Math::Matrix :ALL;
+
+#--Math::Matrix has a built-in operator for kronecker product
+#⊗ or X*
+#
+
+my $A = MM [ [1,2], [3,4] ];
+my $B = MM [ [5,6], [7,8] ];
+
+say $A ⊗ $B;
+
+