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A366758
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a(n) is the sum of the divisors of n!+1.
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2
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3, 3, 4, 8, 31, 133, 832, 5113, 41044, 388800, 3958704, 39916802, 518682390, 6302045232, 90968651712, 1332614649600, 22844265373440, 356226551466344, 7504470340300800, 123358411682195904, 2432902126073962432, 52279222588118377280, 1175121515279802150144
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OFFSET
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0,1
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LINKS
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FORMULA
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EXAMPLE
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a(5) = 133 because the divisors of 5!+1 are {1, 11, 121}.
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MAPLE
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a:=n->numtheory[sigma](n!+1):
seq(a(n), n=0..30);
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MATHEMATICA
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DivisorSigma[1, Range[0, 25]!+1] (* Paolo Xausa, Oct 21 2023 *)
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PROG
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(Python)
from math import factorial
from sympy import divisor_sigma
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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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