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A129115 Number of unrooted unlabeled not necessarily connected triangular maps on a compact closed oriented surface with 2n faces (and thus 3n edges). 1
1, 3, 17, 124, 1618, 33564, 956263, 33736198, 1402665692, 66902717187, 3596481426812, 215049652739982, 14154852098315796, 1016911004448831247, 79174846391508487198, 6640511488761139957873, 596865894849670793348763 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
Equivalently, the number of pair of permutations (sigma,tau) up to simultaneous conjugacy on a set of size 6*n with sigma^3=tau^2=1 with no fixed point.
LINKS
CROSSREFS
Unconnected version of A129114. Unrooted, unconnected version of A062980.
Cf. also A121350, A121352, A005133.
Sequence in context: A216314 A330803 A267736 * A246963 A093460 A187613
KEYWORD
nonn
AUTHOR
Samuel A. Vidal, Mar 30 2007
STATUS
approved

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Last modified April 18 15:48 EDT 2024. Contains 371780 sequences. (Running on oeis4.)