A237111 Triangle read by rows: numerators of coefficients of the Hirzebruch L-polynomials L_n expressing the signature of a 4n-dimensional manifold in terms of its Pontrjagin numbers (as in Hirzebruch Signature Theorem).
1, 7, -1, 62, -13, 2, 381, -71, -19, 22, -3, 5110, -919, -336, 237, 127, -83, 10, 2828954, -503904, -159287, 122523, -40247, 86901, -33863, 8718, -27635, 12842, -1382, 3440220, -611266, -185150, 146256, -62274, 88137, -37290, 22027, 16696, -39341, 10692, -7978, 11880, -4322, 420
Offset: 1
Examples
L_1 = p_1/3. L_2 = (7 p_2-p_1^2)/45. L_3 = (62 p_3-13 p_2 p_1+2 p_1^3)/945. L_4 = (381 p_4-71 p_3 p_1-19 p_2^2+22 p_2 p_1^2-3 p_1^4)/14175. L_5 = (5110 p_5-919 p_4 p_1-336 p_3 p_2+237 p_3 p_1^2+127 p_2^2 p_1-83 p_2 p_1^3+10 p_1^5)/467775. The denominators 3,45,945,14175,467775 follow A171080. The sequence of numerators thus begins 1,7,-1,62,-13,2,381,-71,-19,22,-3,5110,-919,-336,237,127,-83,10,...
References
- F. Hirzebruch, Topological methods in algebraic geometry. Third enlarged edition. Die Grundlehren der Mathematischen Wissenschaften, Band 131 Springer-Verlag New York, Inc., New York 1966, p. 12.
- F. Hirzebruch, The signature theorem: reminiscences and recreation. Prospects in mathematics (Proc. Sympos., Princeton Univ., Princeton, N.J., 1970), pp. 3-31. Ann. of Math. Studies, No. 70, Princeton Univ. Press, Princeton, N.J. 1971.
Links
- Carl McTague, Table of n, a(n) for n = 1..372
- Etienne Ghys and Andrew Ranicki, Signatures in algebra, topology, and dynamics, arXiv preprint arXiv:1512.09258 [math.AT], 2016. (Pg. 78). [From _Tom Copeland_, Aug 24 2019].
- Friedrich Hirzebruch and Matthias Kreck, The concept of genus in topology and complex analysis, Notices of the American Mathematical Society, 56 (6), p. 713-719, 2009, [From _Tom Copeland_, Aug 07 2018].
- Carl McTague, Computing Hirzebruch L-Polynomials.
- Jonas Stelzig, Differential forms and invariants of complex manifolds, arXiv:2503.05983 [math.AT], 2025. See p. 30.
Crossrefs
Cf. A171080.
Programs
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Mathematica
K[Q_,n_Integer] := Module[{z,x}, SymmetricReduction[ SeriesCoefficient[ Product[ComposeSeries[Series[Q[z],{z,0,n}], Series[Subscript[x,i]z,{z,0,n}]],{i,1,n}],n], Table[Subscript[x,i],{i,1,n}], Table[Subscript[p,i],{i,1,n}]][[1]] // FactorTerms]; Table[K[Sqrt[#]/Tanh[Sqrt[#]]&, n],{n,1,5}]
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