OFFSET
1,1
COMMENTS
These are the numbers for which A000164(a(n)) = 4.
a(n) is the n-th largest number which has a representation as a sum of three integer squares (square 0 allowed), in exactly four ways, if neither the order of terms nor the signs of the numbers to be squared are taken into account. The multiplicity of a(n) with order and signs taken into account is A005875(a(n)).
This sequence is a proper subsequence of A000378.
LINKS
Robert Price, Table of n, a(n) for n = 1..1030
MATHEMATICA
Select[Range[0, 1000], Length[PowersRepresentations[#, 3, 2]] == 4 &]
CROSSREFS
KEYWORD
nonn
AUTHOR
Robert Price, Nov 02 2017
EXTENSIONS
Updated Mathematica program to Version 11. by Robert Price, Nov 01 2019
STATUS
approved