login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
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

%I

%S 317206375,6255156277440,30528671745480104,222548537108926490,

%T 154090254047541417984,2000750410187341381632,12197109744970010814464,

%U 897560654227562339370036,17873898563070361396216980,33815935806268253433549768,174633921378662035929052320,957208127608222375829677128

%N 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.

%H Geir Ellingsrud and Stein Arild Stromme, <a href="http://arxiv.org/abs/alg-geom/9411005">Bott's formula and enumerative geometry</a>, J. Amer. Math. Soc. 9 (1996), 175-193; arXiv:alg-geom/9411005, 1994. See Th. 1.2.

%e Triangle begins:

%e 317206375,

%e 6255156277440,

%e 30528671745480104, 222548537108926490,

%e 154090254047541417984, 2000750410187341381632, 12197109744970010814464,

%e 897560654227562339370036, 17873898563070361396216980, 33815935806268253433549768, 174633921378662035929052320, 957208127608222375829677128,

%e ...

%Y Cf. A331445.

%K nonn,tabf

%O 4,1

%A _N. J. A. Sloane_, Jan 22 2020

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified August 16 12:15 EDT 2022. Contains 356168 sequences. (Running on oeis4.)