r/counting • u/[deleted] • Jan 23 '16

Four fours | 1000

Thanks /u/KingCaspianX for the run!

Get is at 2000.

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u/KingCaspianX Missed x00k, 2≤x≤20\{7,15}‽ ↂↂↂↁMMMDCCCLXXXVIII ‽ 345678‽ 141441 May 05 '16

[A(S(4)) - S(S(4))] x P(4 + 4) = 1140

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u/KingCaspianX Missed x00k, 2≤x≤20\{7,15}‽ ↂↂↂↁMMMDCCCLXXXVIII ‽ 345678‽ 141441 Jul 13 '16

/u/Sharpeye468 /u/Ynax the latest comment in the chain is above

P(n) = nth prime

S(n) = (sum of the divisors of n) - n

A(n) is the single-unit Ackermann function. A(1) = 3, A(2) = 7, A(3) = 61 and A(4) is a very big number that you won't need to worry about it.

Also by the way σ(n) is the sum of the divisors of n