Annual Appeal: Please make a donation (tax deductible in USA) to keep the OEIS running. Over 4500 articles have referenced us, often saying "we would not have discovered this result without the OEIS".
There are no self-conjugate partitions of 2, so we set a(2)=0.
Table of n, a(n) for n=0..87.
a(n) = r - (s mod 2), where n = r(r+1)/2 + s with 0 <= s <= r; i.e. r = floor((sqrt(8n+1)-1)/2).
r[n_] := Floor[(Sqrt[8n+1]-1)/2]; s[n_] := n-r[n](r[n]+1)/2; a[n_] := r[n]-Mod[s[n], 2]
Cf. A000700, A067694.
Sequence in context: A012265 A006641 A115756 * A147844 A130634 A053735
Adjacent sequences: A067728 A067729 A067730 * A067732 A067733 A067734
Naohiro Nomoto, Feb 05 2002
Edited by Dean Hickerson, Feb 15 2002