14 lines
393 B
Text
14 lines
393 B
Text
var factorial_primes = Enumerator({|f|
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for k in (1..Inf) {
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if (k!-1 -> is_prime) { f([k, -1]) }
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if (k!+1 -> is_prime) { f([k, +1]) }
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}
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})
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func abr(v) {
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v.len <= 40 ? v : (v.to_s.first(20) + '..' + v.to_s.last(20) + " (#{v.len} digits)")
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}
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factorial_primes.first(30).each_2d {|k,i|
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printf("%3d! %s %d = %s\n", k, (i.sgn < 0 ? '-' : '+'), i.abs, abr(k! + i))
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}
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