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A186808 Numbers n such that there are a prime number of unlabeled distributive lattices with n elements. 0
4, 5, 6, 10, 12, 13, 18, 21, 23, 26 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A lattice which satisfies the identities:

(x^y)V(x^z) = x^(yVz);

(xVy)^(xVz) = xV(y^z)

is said to be distributive.

REFERENCES

Gratzer, G. Lattice Theory: First Concepts and Distributive Lattices. San Francisco, CA: W. H. Freeman, pp. 35-36, 1971.

LINKS

Table of n, a(n) for n=1..10.

FORMULA

{k: A006982(k) is in A000040}.

EXAMPLE

a(10) = 26 because there are 711811 unlabeled distributive lattices with 26 elements, and 711811 is a prime number.

CROSSREFS

Cf. A000040, A006982

Sequence in context: A024565 A327223 A143833 * A114439 A310570 A271146

Adjacent sequences:  A186805 A186806 A186807 * A186809 A186810 A186811

KEYWORD

nonn

AUTHOR

Jonathan Vos Post, Feb 26 2011

STATUS

approved

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Last modified August 12 05:33 EDT 2020. Contains 336438 sequences. (Running on oeis4.)