A358241 - OEIS

A358241

Number of connected Dynkin diagrams with n nodes.

1, 3, 3, 5, 4, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4

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OFFSET

1,2

COMMENTS

The sequence of connected Dynkin diagrams proceeds as {A1}, {A2, B2, G2}, {A3, B3, C3}, {A4, B4, F4, C4, D4}, {A5, B5, C5, D5}, {A6, B6, C6, D6, E6}, {A7, B7, C7, D7, E7}, {A8, B8, C8, D8, E8}, {A9, B9, C9, D9}, ...

REFERENCES

R. W. Carter, Simple groups of Lie type. Vol. 22, John Wiley & Sons, 1989, p. 40.

LINKS

Table of n, a(n) for n=1..94.

Wikipedia, Dynkin diagram

Index entries for linear recurrences with constant coefficients, signature (1).

FORMULA

a(n) = 4 for n > 8.

CROSSREFS

Cf. A060296, A374624.

Sequence in context: A335952 A290284 A258802 * A072820 A204004 A131950

Adjacent sequences: A358238 A358239 A358240 * A358242 A358243 A358244