Data commit

Task/Calkin-Wilf-sequence/Sidef/calkin-wilf-sequence.sidef

@@ -0,0 +1,21 @@
+func calkin_wilf(n) is cached {
+    return 1 if (n == 1)
+    1/(2*floor(__FUNC__(n-1)) + 1 - __FUNC__(n-1))
+}
+
+func r2cw(r) {
+
+    var cfrac = r.as_cfrac
+    cfrac.len.is_odd || return nil
+
+    Num(cfrac.flip.map_kv {|k,v| (k.is_odd ? '0' : '1') * v }.join, 2)
+}
+
+with (20) {|n|
+    say "First #{n} terms of the Calkin-Wilf sequence:"
+    say calkin_wilf.map(1..n)
+}
+
+with (83116/51639) {|r|
+    say ("\n#{r.as_rat} is at index: ", r2cw(r))
+}