OFFSET
1,2
COMMENTS
1 is in the sequence assuming A000385(0) = 0.
The corresponding quotients are 0, 2, 723, 3376, 7196, 48834, 116655, 222646, 263221, 294168, 865608, ...
Includes all the even perfect numbers except for 6 and 28.
The only prime number in the sequence is 3. This follows from formula for A000385 given by Robert Israel. - Luis H. Gallardo, Jun 17 2020
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..500
EXAMPLE
3 is in the sequence since 3 is a divisor for A000385(3-1) = 6.
MATHEMATICA
aQ[n_] := Divisible[5 * DivisorSigma[3, n] - (6n - 1) * DivisorSigma[1, n], 12n]; Select[Range[2*10^5], aQ]
CROSSREFS
KEYWORD
nonn
AUTHOR
Amiram Eldar, Oct 18 2019
STATUS
approved