Abstract
Let p(n) be the number of partitions of the positive integer n. A new q-series identity is presented which witnesses Ramanujan’s observation that \(11|p(11 n +6)\) for all \(n\ge 0\) at one glance. This identity can be derived in a natural way by applying an algorithm to present subalgebras of the polynomial ring \(\mathbb {K}[z]\) as \(\mathbb {K}[z]\)-modules.
Dedicated to our friend Krishna Alladi on his 60th birthday
The research of Radu was supported by the strategic program “Innovatives OÖ 2010 plus” by the Upper Austrian Government in the frame of project W1214-N15-DK6 of the Austrian Science Fund (FWF). Both authors were supported by grant SFB F50-06 of the Austrian Science Fund (FWF)
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Notes
- 1.
For us a \(\mathbb {K}\)-algebra R is a commutative ring R with 1 which is also a vector space over \(\mathbb {K}\).
- 2.
I.e., every element \(p_0(t)+ p_1(t) f + \dots + p_4(t) f^4\) in the module has uniquely determined coefficients \(p_j(t) \in \mathbb {Q}[t]\).
- 3.
Not knowing about Gale’s paper at that time.
- 4.
An entertaining application of this situation is shown in the Numberphile video “How to order 43 Chicken McNuggets”: www.youtube.com/watch?v=vNTSugyS038
- 5.
Such a number is called Frobenius number. Note that 1, 2, 3, 6, and 7 are the other integers not contained in the monoid.
References
G.E. Andrews, P. Paule, A. Riese, MacMahon’s partition analysis III: the omega package. Euro. J. Comb. 22, 887–904 (2001)
G.E. Andrews, P. Paule, A. Riese, MacMahon’s partition analysis VI: a new reduction algorithm. Ann. Comb. 5, 251–270 (2001)
D.S. Dummit, R.M. Foote, Abstract Algebra, 3rd edn. (Wiley, New York, 2005)
D. Gale, Subalgebras of an algebra with a single generator are finitely generated. Proc. Am. Math. Soc. 8, 929–930 (1957)
G. Hardy, P. Aiyar, B. Wilson (eds.), Collected Papers of Srinivasa Ramanujan (Cambridge University Press, Cambridge, 1927). Reprint: AMS Chelsea Publishing (2000)
R. Hemmecke Dancing Samba with Ramanujan Partition Congruences. preprint, 14 pages (2016). (To appear in: J. Symb. Comput.)
D. Kapur, K. Madlener, A Completion Procedure for Computing a Canonical Basis for a \(k\) -Subalgebra, Computers and Mathematics (Springer, Cambridge, MA, 1989), pp. 1–11
G. Köhler, Eta Products and Theta Series Identities (Springer, Berlin, 2011)
P. Paule, C.S. Radu, Partition analysis, modular functions, and computer algebra, Recent Trends in Combinatorics, The IMA Volumes in Mathematics (Springer, Berlin, 2016), pp. 511–544
C.S. Radu, An algorithmic approach to Ramanujan-Kolberg identities. J. Symb. Comput. 68, 1–33 (2014)
S. Ramanujan, Some properties of \(p(n)\), the number of partitions of \(n\). Proc. Camb. Philos. Soc. 19, 207–210 (1919)
L. Robbiano, M. Sweedler Subalgebra bases, in Commutative Algebra (Salvador 1988). Lecture Notes in Mathematics, vol. 1430. (Springer, Berlin, 1990), pp. 61–87
A. Torstensson, Canonical bases for subalgebras on two generators in the univariate polynomial ring. Beiträge Algebra Geom. 43(2), 565–577 (2002)
Acknowledgements
The authors thank the anonymous referee for carefully reading the manuscript and for the suggestions to improve it. Special thanks go to Frank Garvan for very careful editing.
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Paule, P., Radu, CS. (2017). A New Witness Identity for \(\varvec{11\mid p(11n+6)}\) . In: Andrews, G., Garvan, F. (eds) Analytic Number Theory, Modular Forms and q-Hypergeometric Series. ALLADI60 2016. Springer Proceedings in Mathematics & Statistics, vol 221. Springer, Cham. https://doi.org/10.1007/978-3-319-68376-8_34
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DOI: https://doi.org/10.1007/978-3-319-68376-8_34
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