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A354073 Multiply-perfect numbers that are the sum of the divisors of some number. 2
1, 6, 28, 120, 496, 672, 30240, 32760, 523776, 2178540, 23569920, 33550336, 45532800, 142990848, 459818240, 1379454720, 1476304896 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Conjecture: 8128 is only multiply-perfect number that is not in this sequence.
The distinct values of A000203(A066961(n)).
LINKS
EXAMPLE
Number 28 is in the sequence because sigma(12) = 28.
PROG
(Magma) Set(Sort([&+Divisors(m): m in [1..10^7] | IsIntegral(&+Divisors(&+Divisors(m)) / &+Divisors(m))]))
CROSSREFS
Intersection of A007691 and A002191.
Sequence in context: A334410 A065997 A348035 * A171476 A171496 A006516
KEYWORD
nonn,more
AUTHOR
Jaroslav Krizek, May 16 2022
STATUS
approved

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Last modified March 28 16:00 EDT 2024. Contains 371254 sequences. (Running on oeis4.)