Data commit

Task/Self-numbers/Jq/self-numbers.jq

@@ -0,0 +1,35 @@
+def sumdigits: tostring | explode | map([.]|implode|tonumber) | add;
+
+def gsum: . + sumdigits;
+
+def isnonself:
+  def ndigits: tostring|length;
+  . as $i
+  | ($i - ($i|ndigits)*9) as $n
+  | any( range($i-1; [0,$n]|max; -1);
+          gsum == $i);
+
+# an array
+def last81:
+  [limit(81; range(1; infinite) | select(isnonself))];
+
+# output an unbounded stream
+def selfnumbers:
+  foreach range(1; infinite) as $i ( [0, last81];
+    .[0] = false
+    | .[1] as $last81
+    | if $last81 | bsearch($i) < 0
+      then .[0] = $i
+      | if $i > $last81[-1] then .[1] = $last81[1:] + [$i | gsum ] else . end
+      else .
+      end;
+      .[0] | select(.) );
+
+
+"The first 50 self numbers are:", last81[:50],
+"",
+(nth(100000000 - 1;  selfnumbers)
+ | if . == 1022727208
+   then "Yes, \(.) is the 100,000,000th self number."
+   else "No,  \(.i) is actually the 100,000,000th self number."
+   end)