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A296101 Number of maximal cliques in the n-Keller graph. 4
4, 40, 6320, 318322976 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Eric Weisstein's World of Mathematics, Keller Graph
Eric Weisstein's World of Mathematics, Maximal Clique
PROG
(Python)
from itertools import zip_longest
from sympy.ntheory.factor_ import digits
from networkx import empty_graph, find_cliques
def A296101(n):
k = 1<<(n<<1)
G = empty_graph(range(k))
G.add_edges_from((a, b) for a in range(k) for b in range(a) if (s:=tuple(c-d&3 for c, d in zip_longest(digits(a, 4)[-1:0:-1], digits(b, 4)[-1:0:-1], fillvalue=0))).count(2)>0 and s.count(0)<=len(s)-2)
return sum(1 for c in find_cliques(G)) # Chai Wah Wu, Jan 11 2024
CROSSREFS
Sequence in context: A072445 A000841 A059918 * A002677 A119527 A074991
KEYWORD
nonn,hard,more
AUTHOR
Eric W. Weisstein, Dec 04 2017
EXTENSIONS
a(4) from Eric W. Weisstein, Nov 09 2018
STATUS
approved

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Last modified April 23 11:35 EDT 2024. Contains 371912 sequences. (Running on oeis4.)