Menor número triangular con más de n divisores

2 Comentarios

1. Haskell

   import Data.List (genericLength, group) import Data.Numbers.Primes (primeFactors) menorTriangularConAlMenosNDivisores :: Integer -> Integer menorTriangularConAlMenosNDivisores n = head [y | (x,y) <- divisoresTriangulares, x >= n] where divisoresTriangulares = [(numeroDivisores x,x) | x <- triangulares] numeroDivisores :: Integer -> Integer numeroDivisores = product . map ((+1) . genericLength) . group . primeFactors triangulares :: [Integer] triangulares = [x*(x+1) `div` 2 | x <- [1..]]

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   import Data.List (genericLength, group) import Data.Numbers.Primes (primeFactors)        menorTriangularConAlMenosNDivisores :: Integer -> Integer menorTriangularConAlMenosNDivisores n =   head [y | (x,y) <- divisoresTriangulares, x >= n]   where divisoresTriangulares = [(numeroDivisores x,x) | x <- triangulares]   numeroDivisores :: Integer -> Integer numeroDivisores =   product . map ((+1) . genericLength) . group . primeFactors   triangulares :: [Integer] triangulares = [x*(x+1) `div` 2 | x <- [1..]]

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2. En Python

   Python

   from itertools import count, islice from sympy import divisor_count def take(n, xs): """ es la lista formada por los n primeros elementos de xs. Por ejemplo, >>> take(3,count(1)) [1, 2, 3] """ return list(islice(xs, n)) def triangulares(): """ es la lista de los números triangulares. Por ejemplo, >>> take(5,triangulares()) [1, 3, 6, 10, 15] """ return (sum(range(1, n+1)) for n in count(1)) def menorTriangularConAlMenosNDivisores(n): return take(1, (x for x in triangulares() if divisor_count(x) >= n))[0]

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   from itertools import count, islice from sympy import divisor_count     def take(n, xs):     """     es la lista formada por los n primeros elementos de xs. Por     ejemplo,        >>> take(3,count(1))        [1, 2, 3]     """     return list(islice(xs, n))     def triangulares():     """     es la lista de los números triangulares. Por ejemplo,        >>> take(5,triangulares())        [1, 3, 6, 10, 15]     """     return (sum(range(1, n+1)) for n in count(1))     def menorTriangularConAlMenosNDivisores(n):     return take(1, (x for x in triangulares() if divisor_count(x) >= n))[0]

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