d is a noun in 3 : it does not appear in result of 13 13 : is buggy. The tacit version you want is
a =: (a@:a@:<: + ] a@:([ - a@]) <:)`1:@.(<:&2) ----- Original Message ----- From: Louis de Forcrand <[email protected]> To: [email protected] Sent: Tuesday, December 27, 2016 6:07 PM Subject: [Jprogramming] Strange 13 : '...' behavior From: http://rosettacode.org/wiki/Hofstadter-Conway_$10,000_sequence <http://rosettacode.org/wiki/Hofstadter-Conway_$10,000_sequence> JVERSION Engine: j805/j64/darwin Beta-12: commercial/2016-09-30T16:11:35 Library: 8.05.07 Platform: Darwin 64 Installer: J805 install InstallPath: /users/louisdeforcrand/applications/j64-805 Contact: www.jsoftware.com a=: 3 : '(a a d)+a y-a d=.<:y'`1:@.(<:&2) a"0>:i.10 NB. correct behavior 1 1 2 2 3 4 4 4 5 6 a=: 13 : '(a a d)+a y-a d=.<:y'`1:@.(<:&2) a"0>:i.10 NB. incorrect behavior 1 1 2 3 4 5 6 7 8 9 a (] (([: a a) + [: a [ - a) <:)`1:@.(<:&2) Anybody know what’s going on? Louis ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
