

A291209


Numbers n such that psi(n) is the sum of proper divisors of n where psi(n) = A001615(n).


1



9504, 16560, 41400, 5048568, 10889856, 11941344, 16255080, 131473152, 5517818880, 107561120688, 612014161920
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OFFSET

1,1


COMMENTS

Or numbers n such that sigma(n) = psi(n) + n where psi(n) = A001615(n) and sigma(n) = A000203(n).
9504 = 2^5*3^3*11 is the smallest number with this property.


LINKS



EXAMPLE

16560 is a term because sigma(16560) = 58032 and psi(16560) = 41472; sigma(16560)  psi(16560) = 16560.


PROG

(PARI) a001615(n) = n*sumdivmult(n, d, issquarefree(d)/d);


CROSSREFS



KEYWORD

nonn,more


AUTHOR



EXTENSIONS



STATUS

approved



