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A095682 Primitive 1+prime power perfect numbers: if n=Product p_i^r_i then 1PPsigma(n)= Product {Sum p_i^r_i, 1<=s_i<=r_i, s_i is one or prime} 1PPsigma(n)=2*n. 0
36, 392, 152352, 6072901632, 1444601174400 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Factorizations: 2^2*3^2, 2^3*7^2, 2^5*3^2*23^2, 2^13*3^2*7^2*41^2, 2^7*3^5*5^2*29^2*47^2. No squarefree solution exists.
LINKS
EXAMPLE
1PPsigma(2^5*3^3)=(2+2^2+2^3+2^5)*(3+3^2+3^3)=1794
CROSSREFS
Cf. A096290.
Sequence in context: A034686 A160280 A307959 * A083811 A086575 A203027
KEYWORD
nonn
AUTHOR
STATUS
approved

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Last modified April 29 18:29 EDT 2024. Contains 372114 sequences. (Running on oeis4.)