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%I #5 Nov 25 2024 20:45:28
%S 1,2,6,16,45,129,367,1081,3098,9291,26788,81341,235729,722479,2102856,
%T 6492146,18965527,58898531,172600126,538640825,1582733185,4959648919,
%U 14607576158,45935431662,135571479679,427621459608,1264356405112,3998682343629,11842126315245,37540318975749
%N Number of connected achiral planar maps with an external face and n internal triangular faces.
%o (PARI) A378341seq(30) \\ See PARI link in A378340 for program code.
%Y Column sums of A378340.
%Y Cf. A378337, A378339, A378342.
%K nonn,new
%O 1,2
%A _Andrew Howroyd_, Nov 25 2024