Talk:Spy numbers

Spy Numbers
Spy Numbers are the numbers whose sum of digits and product of digits are the same. For example, 2411 (2+4+1+1=8 & 2*4*1*1=8). What if we explain that topic and provide examples and additional information in this page. Telectision (talk) 13:36, 16 February 2024 (UTC)


 * We would need to create that page, with proper sources, etc. Would you like to create a page for it? I can help out, I don't know enough about spy numbers, but they seem a worthwhile topic : ) Radlrb (talk) 00:07, 18 February 2024 (UTC)
 * Spy numbers certainly exist: I've found several sources, but none I'd consider reliable. They don't seem to be in OEIS.  Rather than numbers, they are really spy sets: {1,2,3}, {1,1,2,4}, etc.  There's no particular ordering. (If 1124 is a spy number then so are its anagrams 1142, 1214, etc.) The choice of 10 as the radix is arbitrary.  (Why not 11248 = 596, etc.?  What happens if a number in the set > 9?)  Most numbers can be made spy by appending sufficient ones.  For example, 34 isn't a spy number but 1,111,134 is: I just added (3×4)–(3+4) ones.  I'm not sure that it's a notable property. Certes (talk) 18:02, 18 February 2024 (UTC)
 * It does not seem too notable on its own, but it does pop up a lot on simple searches, so I am wondering where that information is coming from. I'm sure some nice properties can come from sets of spy numbers, at least that is the inclination I get. I don't know much else on them. Radlrb (talk) 18:40, 20 February 2024 (UTC)