OFFSET
1,1
LINKS
T. D. Noe, Table of n, a(n) for n = 1..10000
MATHEMATICA
nn = 10^3; ps = Prime[Range[PrimePi[Sqrt[nn]]]]; t = Flatten[Table[ps[[i]]^2 + ps[[j]]^2 + ps[[k]]^2 + ps[[l]]^2, {i, Length[ps]}, {j, i, Length[ps]}, {k, j, Length[ps]}, {l, k, Length[ps]}]]; t = Select[t, # <= nn &]; Union[t]
CROSSREFS
KEYWORD
nonn
AUTHOR
T. D. Noe, Jul 29 2012
STATUS
approved