14 lines
284 B
R
14 lines
284 B
R
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#This is equivalent to n*(n^2+1)/2, but it's easier to see where this form comes from
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magic <- function(n) sum(1:(n^2))/n
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sapply(3:22, magic)
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magic(1003)
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inv_magic <- function(lower){
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n <- 3
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while(magic(n)<=lower) n <- n+1
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return(n)
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}
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sapply(cumprod(rep(10, 20)), inv_magic)
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