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%I #13 Oct 17 2022 15:34:17
%S 0,1,19,99,310,760,1556,2863,4849,7713,11702,17077,24066,33021,44272,
%T 58180,75148,95526,119758,148489,181924,220796,265519,316736,375006,
%U 441061,515467,598680,691761,795410,909971,1036745,1176108,1329286,1496711,1679852,1879036,2095235
%N Number of scalene triangles, distinct up to congruence, on a centered hexagonal grid of size n.
%C A centered hexagonal grid of size n is a grid with A003215(n-1) points forming a hexagonal lattice.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/HexNumber.html">Hex Number</a>.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/ScaleneTriangle.html">Scalene Triangle</a>.
%F a(n) = A241231(n) - A241237(n).
%e For n = 2 the only kind of non-congruent scalene triangles is the following:
%e /. *
%e * . *
%e \. .
%Y Cf. A190313, A241227.
%K nonn
%O 1,3
%A _Martin Renner_, Apr 17 2014
%E a(7) from _Martin Renner_, May 31 2014
%E a(8)-a(13) from _Giovanni Resta_, May 31 2014
%E More terms from _Bert Dobbelaere_, Oct 17 2022
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