A271078 - OEIS

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A271078

Number of non-isomorphic atomic lattices on n nodes.

0

0, 1, 1, 0, 1, 1, 2, 4, 9, 22, 59, 181

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OFFSET

0,7

LINKS

Table of n, a(n) for n=0..11.

PROG

(SageMath)

for i in range(0, 12):

n = 0

for P in Posets(i):

if P.is_lattice():

L = LatticePoset(P)

if L.is_atomic():

n += 1

print(n)

CROSSREFS

Sequence in context: A193361 A294281 A293854 * A292790 A278691 A159329

Adjacent sequences: A271075 A271076 A271077 * A271079 A271080 A271081

KEYWORD

nonn,hard,more

AUTHOR

Jori Mäntysalo, Mar 30 2016

STATUS

approved