A213443 - OEIS

A213443

a(0)=5, thereafter a(n) = chromatic number (or Heawood number) Chi(n) of surface of genus n.
(Formerly N1533)

5, 7, 8, 9, 10, 11, 12, 12, 13, 13, 14, 15, 15, 16, 16, 16, 17, 17, 18, 18, 19, 19, 19, 20, 20, 20, 21, 21, 21, 22, 22, 22, 23, 23, 23, 24, 24, 24, 24, 25, 25, 25, 25, 26, 26, 26, 27, 27, 27, 27, 28, 28, 28, 28, 28, 29, 29, 29, 29, 30, 30, 30, 30, 31, 31, 31, 31, 31, 32, 32

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,1

COMMENTS

This is what A000934 would have looked like if the four-color conjecture had turned out to be false.

REFERENCES

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

LINKS

Table of n, a(n) for n=0..69.

CROSSREFS

Cf. A000934.

Sequence in context: A338595 A254274 A068001 * A302980 A242963 A191846

Adjacent sequences: A213440 A213441 A213442 * A213444 A213445 A213446

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Jun 12 2012

STATUS

approved