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A331446 Irregular triangle read by rows: numbers of twisted cubics on Calabi-Yao hypersurfaces. Row n refers to hypersurfaces of degree n+1 in P^n, the entries in that row being indexed by partitions of n-4. 0
317206375, 6255156277440, 30528671745480104, 222548537108926490, 154090254047541417984, 2000750410187341381632, 12197109744970010814464, 897560654227562339370036, 17873898563070361396216980, 33815935806268253433549768, 174633921378662035929052320, 957208127608222375829677128 (list; graph; refs; listen; history; text; internal format)
OFFSET

4,1

LINKS

Table of n, a(n) for n=4..15.

Geir Ellingsrud and Stein Arild Stromme, Bott's formula and enumerative geometry, J. Amer. Math. Soc. 9 (1996), 175-193; arXiv:alg-geom/9411005, 1994. See Th. 1.2.

EXAMPLE

Triangle begins:

317206375,

6255156277440,

30528671745480104, 222548537108926490,

154090254047541417984, 2000750410187341381632, 12197109744970010814464,

897560654227562339370036, 17873898563070361396216980, 33815935806268253433549768, 174633921378662035929052320, 957208127608222375829677128,

...

CROSSREFS

Cf. A331445.

Sequence in context: A105005 A157789 A331445 * A184573 A112429 A104923

Adjacent sequences:  A331443 A331444 A331445 * A331447 A331448 A331449

KEYWORD

nonn,tabf

AUTHOR

N. J. A. Sloane, Jan 22 2020

STATUS

approved

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Last modified July 5 15:05 EDT 2022. Contains 355099 sequences. (Running on oeis4.)