A011990 - OEIS

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A011990

Covering numbers C(n,9,5) (next term is <= 19).

0

1, 6, 7, 12

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

OFFSET

9,2

REFERENCES

CRC Handbook of Combinatorial Designs, 1996, p. 263.

LINKS

Table of n, a(n) for n=9..12.

D. Gordon, La Jolla Repository of Coverings

Index entries for covering numbers

CROSSREFS

Sequence in context: A228948 A297128 A035110 * A105085 A287412 A097354

Adjacent sequences: A011987 A011988 A011989 * A011991 A011992 A011993

KEYWORD

nonn,hard

AUTHOR

N. J. A. Sloane

STATUS

approved