OFFSET
1,1
COMMENTS
The sum of divisors of 2m^2 [twice a square] always gives remainder r = 3 modulo 6. See A097022.
LINKS
T. D. Noe, Table of n, a(n) for n = 1..10000
FORMULA
a(n) = 3*A065766(n).
Sum_{k=1..n} a(k) ~ c * n^3, where c = 12*zeta(3)/Pi^2 = 1.461525... . - Amiram Eldar, Oct 28 2022
MATHEMATICA
DivisorSigma[1, 2*Range[50]^2] (* Harvey P. Dale, Sep 06 2015 *)
PROG
(PARI) { for (n=1, 10000, write("b065765.txt", n, " ", sigma(2*n^2)) ) } \\ Harry J. Smith, Oct 30 2009
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Nov 19 2001
STATUS
approved