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A112390 Triangle read by rows: T(n,k) is the number of ways of building a building of height k using n 2 X 4 LEGO blocks, counted up to symmetry (for 2 <= k <= n).

%I A112390 #26 Jun 01 2024 11:14:23
%S A112390 24,500,1060,11707,59201,48672,248688,3203175,4425804,2238736,7946227,
%T A112390 162216127,359949655,282010252,102981504
%N A112390 Triangle read by rows: T(n,k) is the number of ways of building a building of height k using n 2 X 4 LEGO blocks, counted up to symmetry (for 2 <= k <= n).
%D A112390 Anthony Lane, The Joy of Bricks, The New Yorker, Apr 27-May 04, 1998, pp. 96-103.
%H A112390 B. Durhuus and S. Eilers, <a href="https://arxiv.org/abs/math/0504039">On entropy of LEGO</a>, arXiv:math/0504039 [math.CO], 2005.
%H A112390 S. Eilers, <a href="http://www.math.ku.dk/~eilers/lego.html">A LEGO Counting problem</a>.
%H A112390 <a href="/wiki/Index_to_OEIS:_Section_Lc#LEGO">Index entry for sequences related to LEGO blocks</a>.
%e A112390 Triangle begins:
%e A112390        24;
%e A112390       500,      1060;
%e A112390     11707,     59201,     48672;
%e A112390    248688,   3203175,   4425804,   2238736;
%e A112390   7946227, 162216127, 359949655, 282010252, 102981504;
%Y A112390 Cf. A112389.
%K A112390 nonn,tabl,more
%O A112390 2,1
%A A112390 _N. J. A. Sloane_, Dec 06 2005
%E A112390 Thanks to _Gerald McGarvey_, _Christian Schroeder_ and _Jud McCranie_, who contributed to this entry.