OFFSET
1,2
LINKS
Robert Israel, Table of n, a(n) for n = 1..2000
FORMULA
It appears that a(n) ~ 2^(2/3) * Pi^2 * n^2/(9 * Gamma(2/3)^3). - Robert Israel, Sep 19 2024
MAPLE
M:= 200: # to get a(1) .. a(M)
N:= 2*N^3:
A:=sort(convert({seq(seq(x^3 + y^3, y = 1 .. floor((N-x^3)^(1/3))), x=1..floor(N^(1/3)))}, list)):
filter:= proc(n) local F;
if n::odd then return false fi;
F:= ifactors(n/2)[2][.., 2] mod 3;
andmap(`=`, F, 0)
end proc:
select(t -> filter(A[t]), [$1..nops(A)]); # Robert Israel, Sep 19 2024
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved