

A089040


Number of primitive partition identities with largest part n.


0



1, 5, 15, 47, 102, 276, 578, 1261, 2465, 5362, 9285, 18900, 33269, 58171, 99328, 181514, 287239, 502116, 775710, 1239710, 1956334, 3210736, 4660786, 7297823, 10997235, 16536803
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OFFSET

2,2


REFERENCES

U.U. Haus, M. Koeppe and R. Weismantel, A Primal AllInteger Algorithm Based on Irreducible Solutions, Math. Programming, Series B, 96 (2003), no. 2, 205246
B. Sturmfels and R. R. Thomas, Variation of Cost Functions in Integer Programming, Mathematical Programming 77 (1997), 357387


LINKS

Table of n, a(n) for n=2..27.
M. Koeppe, Primitive Partition Identities


EXAMPLE

a(3)=5 because we can write 2=1+1, 3=1+2, 3=1+1+1, 3+1=2+2, 3+3=2+2+2.


CROSSREFS

A007343 counts the homogeneous PPIs only, i.e. the same number of summands appears on the lhs and rhs.
Sequence in context: A197237 A307242 A296545 * A331237 A184262 A126944
Adjacent sequences: A089037 A089038 A089039 * A089041 A089042 A089043


KEYWORD

nonn


AUTHOR

Matthias Koeppe (mkoeppe(AT)mail.math.unimagdeburg.de), Dec 03 2003


STATUS

approved



