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%I #12 May 31 2014 10:39:29
%S 0,12,648,6084,30444,107376,302916,732024,1576728,3111012,5724852,
%T 9952620,16509336,26321160,40567872,60724104,88605480,126413772,
%U 176788476,242874756,328359624,437553360
%N Number of scalene triangles 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) = A241223(n) - A241228(n).
%Y Cf. A190312.
%K nonn,more
%O 1,2
%A _Martin Renner_, Apr 17 2014
%E a(7) from _Martin Renner_, May 31 2014
%E a(8)-a(22) from _Giovanni Resta_, May 31 2014