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A343093
Number of rooted toroidal maps with n edges and no isthmuses.
3
1, 14, 159, 1680, 17147, 171612, 1696491, 16631840, 162090756, 1572801142, 15210259585, 146710561296, 1412132981778, 13569013500024, 130199055578307, 1247825314752768, 11947157409479180, 114288613130155608, 1092495810452593564, 10436544808441964352
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OFFSET
2,2
LINKS
Andrew Howroyd,
Table of n, a(n) for n = 2..100
FORMULA
Conjectural g.f.: A(x) = ( Sum_{n >= 1} (1/4)*binomial(4*n, n)*x^n )^2. -
Peter Bala
, Jul 24 2025
CROSSREFS
Row sums of
A343092
.
Cf.
A224274
,
A343091
.
Sequence in context:
A122187
A268946
A383946
*
A383783
A229611
A282043
Adjacent sequences:
A343090
A343091
A343092
*
A343094
A343095
A343096
KEYWORD
nonn
AUTHOR
Andrew Howroyd
, Apr 04 2021
STATUS
approved
