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%I #27 Aug 13 2020 18:27:32
%S 0,2,4,6,8,11,14,17,21,24,28,32,37,41,46,50,55,60,66,71
%N Side length of smallest square containing n dominoes with short side lengths 1, 2, ..., n.
%C A domino with short side length k has dimensions k X 2k.
%C Terms a(5) to a(13) were found by Erich Friedman in 1998, a(14) to a(19) by Erich Friedman in January 2004.
%C a(n) >= ceiling(sqrt(n*(n + 1)*(2n + 1)/3)).
%H Erich Friedman, <a href="https://erich-friedman.github.io/packing/domino/">Dominoes in Squares</a>
%e Illustration:
%e .
%e . - - a - - - a a - - - - - - - - a a b b
%e . a a a - - - b b b b - - c c c c c c b b
%e . b b b b b b b b - - c c c c c c b b
%e . b b b b c c c c c c c c c c c c b b
%e . c c c c c c d d d d d d d d
%e . c c c c c c d d d d d d d d
%e . d d d d d d d d
%e . d d d d d d d d
%e .
%e . 2 4 6 8
%e .
%Y Cf. A211372, A238259.
%K nonn,hard,more
%O 0,2
%A _Ivan Panchenko_, Feb 15 2014