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A280420
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Product of divisors of n!.
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2
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1, 1, 2, 36, 331776, 42998169600000000, 7244150201408990671659859968000000000000000, 1182813011613388022005884215741990164001544397058025540221953280041975323323006976000000000000000000000000000000
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OFFSET
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0,3
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LINKS
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FORMULA
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MAPLE
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mul(d, d=numtheory[divisors](n!)) ;
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MATHEMATICA
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Table[(n!)^(DivisorSigma[0, n!]/2), {n, 0, 10}]
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PROG
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(Python)
from math import isqrt, factorial
from sympy import divisor_count
def A280420(n): return (lambda m:isqrt(m)**c if (c:=divisor_count(m)) & 1 else m**(c//2))(factorial(n)) # Chai Wah Wu, Jun 25 2022
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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