# How can I add sequences of numbers quickly? like 1,2,3,4,5,6,7,8,9 + 9,8,7,6,5,4,3,2,1 all equal 10?

I want to play with numbers but it uses a lot of paper and repetitive mental addition to add together sequences like these that don't all add up to the same number. Also if you know of a way I could add tables(sets of sequences) easily that would be awesome too. and if I could have it all be able to do it in mod9:-D

here is a description of the same thing but more detailed

"I would love a way to be able to pull up a mod9 multiplication table and then add it to another of the same table and see what that looks like in mod9. this takes lots of time manually, and with some quick coding would be a great addition to wolfram alpha:-)

also then I could type in "mod9 multiplication series 1" and refer to 123456789. and mod9 multseries8 and refer to 876543219. ect...

-having a way to then add these series like when adding the tables would be great. so I could say "mod9 m1+m8" and it would show me m9(m9=999999999)

You could also be able to say like "doubling pattern starting from 1 in mod9" and then I would get 1,2,4,8,7(16),5(32),1(64),2(128),4,8,7,5...

-then a cool input might be "(doubling pattern1)+(m9+1)" and it would show me

"

1,2,4,8,7,5,1,2,4,8,7,5

1,1,1,1,1,1,1,1,1,1,1,1

2,3,5,9,8,6,2,3,5,9,8,6

"

-another input might be "whats the different between m3 and m6?""

Thanks

### 1 Answer

- Curt MonashLv 71 decade agoFavorite Answer
Well, it's pretty easy to do modular arithmetic in a program like Excel.

I forget whether there's an explicit Mod or Remainder function, but if not you could quickly synthesize one.

If you want K (mod N), just look at K - N * Floor (K/N), where Floor is the integer-part function.

But probably the Remainder function exists anyway.

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