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A120420 Number of graphs of functions with n triple points. 2
1, 2, 19, 428, 17746, 1178792, 114892114, 15465685088, 2750970320776, 625218940868432, 176816078759177584, 60910324282361987648, 25113805147553980835056, 12212353714587611449244672 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

REFERENCES

V. I. Arnold, Smooth function statistics, Funct. Anal. Other. Math., 1 (2006), 111-118.

Liviu I. Nicolaescu, Counting Morse functions on the 2-sphere, arXiv:math/0512496.

LINKS

Vladeta Jovovic (vladeta(AT)eunet.rs), Feb 22 2008, Table of n, a(n) for n = 1..21

FORMULA

Nicolaescu gives a g.f.

a(n) >= A135487(n).

CROSSREFS

Sequence in context: A090308 A110818 A155927 * A158099 A015204 A086976

Adjacent sequences:  A120417 A120418 A120419 * A120421 A120422 A120423

KEYWORD

nonn

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com), Feb 21 2008

EXTENSIONS

More terms from Vladeta Jovovic (vladeta(AT)eunet.rs), Feb 22 2008

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Last modified February 16 23:45 EST 2012. Contains 205978 sequences.