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A018981 Cycle class sequence c(2n) (the number of true cycles of length 2n in which a certain node is included) for zeolite AST = AlPO4-16 [ Al20P20O80 ] .4 R . 16 H2O. 0
0, 6, 24, 192, 924, 6432, 39096, 251712, 1601904, 10498200, 69861552, 472556352, 3225921672, 22211011704, 154049303808 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,2

LINKS

Table of n, a(n) for n=2..16.

Georg Thimm, Cycle sequences of crystal structures.

Georg Thimm, Personal website (archived).

Georg Thimm, A graph theoretical approach to the analysis, comparison, and enumeration of crystal structures, Dissertation, Goethe University Frankfurt, Germany, 2008.

Georg Thimm and W. E. Klee, Zeolite cycle sequences, Zeolites, 19(5-6) (1997), 422-424.

CROSSREFS

Sequence in context: A293488 A038033 A064049 * A052594 A320944 A277985

Adjacent sequences:  A018978 A018979 A018980 * A018982 A018983 A018984

KEYWORD

nonn,more

AUTHOR

Georg Thimm (mgeorg(AT)ntu.edu.sg)

EXTENSIONS

a(11)-a(16) from Sean A. Irvine, Mar 12 2019

STATUS

approved

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Last modified December 5 10:45 EST 2019. Contains 329751 sequences. (Running on oeis4.)