June 2018 Update

2018-06-22 20:57:24 +00:00 · 2018-06-22 20:57:24 +00:00 · 22f33d4004
commit 22f33d4004
parent ba8067c3b7
5278 changed files with 84726 additions and 14379 deletions
--- a/Task/Catalan-numbers-Pascals-triangle/Factor/catalan-numbers-pascals-triangle.factor
+++ b/Task/Catalan-numbers-Pascals-triangle/Factor/catalan-numbers-pascals-triangle.factor
@ -0,0 +1,14 @@
+USING: arrays grouping io kernel math prettyprint sequences ;
+IN: rosetta-code.catalan-pascal
+
+: next-row ( seq -- seq' )
+    2 clump [ sum ] map 1 prefix 1 suffix ;
+
+: pascal ( n -- seq )
+    1 - { { 1 } } swap [ dup last next-row suffix ] times ;
+
+15 2 * pascal [ length odd? ] filter [
+    dup length 1 = [ 1 ]
+    [ dup midpoint@ dup 1 + 2array swap nths first2 - ] if
+    pprint bl
+] each drop