23 lines
441 B
R
23 lines
441 B
R
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library(numbers)
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MAX <- 5e7
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primes <- Primes(1, ceiling(sqrt(MAX)))
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potfilter <- function(numbers, filter)
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numbers[numbers < filter]
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sums <- sapply(
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potfilter(primes^4, MAX),
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function(x) {
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sapply(
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potfilter(primes^3, MAX),
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function(y) {
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sapply(primes^2, function(z) {
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x+y+z
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})
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}
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)
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}
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)
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length(unique(sums[sums<MAX]))
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