OFFSET
1,2
COMMENTS
Every 7*p with p prime <> 7 is a term because 7*p / sigma(tau(7*p)) = p (see example).
EXAMPLE
35 = 7 * 5, tau(35) = 4, sigma(tau(35)) = sigma(4) = 4 + 2 + 1 = 7 and 35/7 = 5 hence 35 is a term.
MAPLE
with(numtheory) filter:= m -> m/sigma(tau(m)) = floor(m/sigma(tau(m))) : select(filter, [$1..600]);
MATHEMATICA
Select[Range[600], Divisible[#, DivisorSigma[1, DivisorSigma[0, #]]] &] (* Amiram Eldar, Jul 27 2020 *)
PROG
(PARI) isok(m) = !(m % sigma(numdiv(m))); \\ Michel Marcus, Jul 29 2020
CROSSREFS
KEYWORD
nonn
AUTHOR
Bernard Schott, Jul 27 2020
STATUS
approved