21 lines
443 B
Text
21 lines
443 B
Text
func calkin_wilf(n) is cached {
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return 1 if (n == 1)
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1/(2*floor(__FUNC__(n-1)) + 1 - __FUNC__(n-1))
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}
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func r2cw(r) {
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var cfrac = r.as_cfrac
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cfrac.len.is_odd || return nil
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Num(cfrac.flip.map_kv {|k,v| (k.is_odd ? '0' : '1') * v }.join, 2)
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}
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with (20) {|n|
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say "First #{n} terms of the Calkin-Wilf sequence:"
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say calkin_wilf.map(1..n)
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}
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with (83116/51639) {|r|
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say ("\n#{r.as_rat} is at index: ", r2cw(r))
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}
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