OFFSET
1,3
COMMENTS
There are no such partitions of 2n+1.
EXAMPLE
For n=6 the five partitions {6,6}, {5,4,3}, {4,3,2,1,1,1}, {4,2,2,2,2} and {3,1,1,1,1,1,1,1,1,1} and no others, satisfy the stated requirements, so a(12)=5.
MATHEMATICA
(* first do *) Needs["DiscreteMath`Combinatorica`"] (* then *) f[n_] := Block[{p = Partitions[n], l = PartitionsP[n], c = 0, k = 2}, While[k < l + 1, If[ p[[k, 1]]^2 == Plus @@ (Drop[p[[k]], 1]^2), c++ ]; k++ ]; c]; Table[ f[n], {n, 67}] (* Robert G. Wilson v, Sep 23 2004 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
John W. Layman, Sep 22 2004
EXTENSIONS
More terms from Robert G. Wilson v, Sep 23 2004
STATUS
approved