OFFSET
1,1
COMMENTS
It seems as if 33 is the largest number with no such representation. 60 seems to be the largest one with exactly one representation.
More generally, see A080673 for the largest number with n such representations. - M. F. Hasler, Mar 04 2016
LINKS
Hagen von Eitzen, Table of n, a(n) for n = 1..78107
EXAMPLE
a(4) = 62 because there are exactly four representations as a sum of 5 squares: 62 = 1+4+4+4+49 = 1+4+16+16+25 = 4+4+4+25+25 = 4+4+9+9+36.
MATHEMATICA
f[k_] := f[k] = Length[Select[PowersRepresentations[k, 5, 2], #[[1]] > 0 &]]; a[n_] := (k = 1; While[f[k++] != n]; k-1); Array[a, 54] (* Jean-François Alcover, Apr 26 2011 *)
f[n_] := f[n] = Block[{c = Range@ Sqrt@ n^2}, Length@ IntegerPartitions[n, {5}, c]]; t = Array[f, 50000, 0]; Table[ Position[t, n, 1, 1], {n, 190}] - 1 (* Robert G. Wilson v, Jun 01 2014 *)
CROSSREFS
KEYWORD
easy,nice,nonn
AUTHOR
Rainer Rosenthal, Mar 01 2003
EXTENSIONS
More terms from Reinhard Zumkeller, Apr 26 2004
Definition adjusted to cope with otherwise undefined values and b-file extended by Hagen von Eitzen, Jun 05 2014
STATUS
approved