OFFSET
1,1
COMMENTS
All terms == 1,3,5 or 9 (mod 10). - Robert Israel, Mar 20 2018
REFERENCES
G. Tenenbaum, pp. 268ff of R. L. Graham et al., eds., Mathematics of Paul Erdős I.
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
MAPLE
N:= 10000: # to get all terms <= N
g:= n -> n^2+(n+1)^2:
sort(convert({seq(seq(g(q)*g(r), r = 1 .. floor((sqrt(2*N/g(q)-1)-1)/2)), q=1 .. floor((sqrt(2*N/5-1)-1)/2))}, list)); # Robert Israel, Mar 20 2018
MATHEMATICA
With[{nn=30}, Select[Union[Flatten[Table[(q^2+(q+1)^2)(r^2+(r+1)^2), {q, nn}, {r, q}]]], #<=5(nn^2+(nn+1)^2)&]] (* Harvey P. Dale, Jan 28 2019 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved