Those 6 terms were first found by Lander and Parkin in 1967.
Table of n, a(n) for n=1..6.
Tanya Khovanova, Non Recursions
Cf. A006560, A058362.
Sequence in context: A015380 A250458 A038131 * A058362 A213463 A175321
Adjacent sequences: A081731 A081732 A081733 * A081735 A081736 A081737
Benoit Cloitre, Apr 06 2003