Pandigital fun - Printable Version +- HP Forums (https://www.hpmuseum.org/forum) +-- Forum: Not HP Calculators (/forum-7.html) +--- Forum: Not remotely HP Calculators (/forum-9.html) +--- Thread: Pandigital fun (/thread-8210.html) Pandigital fun - Paul Dale - 04-20-2017 09:42 AM Have a look at this paper. Pandigital representations of numbers up to 11111 where the digits are in ascending or descending order and only basic operations are used. Code: `41 = 12 − 34 − 5 + 67 − 8 + 9` Pauli RE: Pandigital fun - pier4r - 04-20-2017 10:48 AM Just saw a video on numberphile about this and I wanted to create a programming challenge (limited to 3 digits numbers, that is already enough for a calculator). But you spoiled it . Well no, I can do it nevertheless using the paper for checking the solutions. RE: Pandigital fun - Gerson W. Barbosa - 04-20-2017 12:53 PM (04-20-2017 10:48 AM)pier4r Wrote:  Just saw a video on numberphile about this and I wanted to create a programming challenge (limited to 3 digits numbers, that is already enough for a calculator). What about another kind of fun? Evaluate this: Evaluate that: Random order and ascending order. Descending order still missing... RE: Pandigital fun - pier4r - 04-20-2017 02:30 PM Well Gerson, while computing Pi in that way is fun, to me it is already a challenge to break down numbers. In particular I like the idea of using only one digit and the four operations (plus powers and parentheses). For example given 998 and 1. 998 = (11-1)^(1+1+1)- 1 -1 The hard part: having the smallest number of 1s used on the right side. And then doing the same with 2, 3 and so on. The mentioned video links to a paper with the solutions. It is still a nice challenge, so I will formalize it in some days. Calculator wise (we don't want to use the modern home supercomputers, do we?)