1,3

Solutions differing only in the order of the x_i are counted as distinct.

All denominators in the expansion 1 = 1/x_1 + ... 1/x_n are bounded by the n-th term of Sylvester's sequence A000058(n) - Max Alekseyev (maxale(AT)gmail.com), Dec 30 2003

R. K. Guy, Unsolved Problems in Number Theory, D11.

D. Singmaster, ``The number of representations of one as a sum of unit fractions,'' unpublished manuscript, 1972.

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Index entries for sequences related to Egyptian fractions

58-th Putnam Mathematical Competition, 1997, Problem A-5

For n=3 the 10 solutions are {2,3,6} (6 ways), {2,4,4} (3 ways), {3,3,3} (1 way).

Cf. A002966, A006585.

Cf. A000058.

Sequence in context: A120596 A112364 A057408 this_sequence A007698 A007699 A024291

Adjacent sequences: A002964 A002965 A002966 this_sequence A002968 A002969 A002970

nonn,nice,hard

N. J. A. Sloane (njas(AT)research.att.com).

a(7) from Jud McCranie (j.mccranie(AT)comcast.net).

a(8) from John Dethridge, Jan 11, 2004