Talk:Strange plus numbers
From Rosetta Code
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- It seems that strange numbers and strange plus numbers have been coined by CalmoSoft. The web seems to know nothing of them. 498 is a 'strange plus number' because 4+9 is prime and 9+8 is prime. Every sum of adjacent pairs of digits must be prime. --Chunes (talk) 08:13, 23 February 2021 (UTC)
- There's something here but the definition is not the same as CalmoSoft's. Curiously, he always misses off the first column of output in his Ring solutions.
- Hope there's not going to be too many of these - don't want another unixdict.txt situation! --PureFox (talk) 10:17, 23 February 2021 (UTC)
- @Chunes If the condition is "the sum of two consecutive digits is always prime", then one-digit numbers should be considered strange (it's vacuously true that for all pairs of consecutive digits the sum is prime). In the C solution I added a condition on n<10 to force them to be non-strange, but it's easy to remove. We could change the task to solve the general solution and decide what to do with one-digit numbers (I think it's better to have them strange). Bastet (talk) 13:33, 24 February 2021 (UTC)
Hello PureFox. I changed the code as you suggested (CalmoSoft)