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A237886 Side length of smallest square containing n dominoes with short side lengths 1, 2, ..., n. 1
0, 2, 4, 6, 8, 11, 14, 17, 21, 24, 28, 32, 37, 41, 46, 50, 55, 60, 66, 71 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

A domino with short side length k has dimensions k X 2k.

Terms a(5) to a(13) were found by Erich Friedman in 1998, a(14) to a(19) by Erich Friedman in January 2004.

a(n) >= ceiling(sqrt(n*(n + 1)*(2n + 1)/3)).

LINKS

Table of n, a(n) for n=0..19.

Erich Friedman, Dominoes in Squares

EXAMPLE

Illustration:

.

. - -    a - - -    a a - - - -    - - - - a a b b

. a a    a - - -    b b b b - -    c c c c c c b b

.        b b b b    b b b b - -    c c c c c c b b

.        b b b b    c c c c c c    c c c c c c b b

.                   c c c c c c    d d d d d d d d

.                   c c c c c c    d d d d d d d d

.                                  d d d d d d d d

.                                  d d d d d d d d

.

.  2        4            6                8

.

CROSSREFS

Cf. A211372, A238259.

Sequence in context: A092777 A186380 A006463 * A212555 A328787 A339573

Adjacent sequences:  A237883 A237884 A237885 * A237887 A237888 A237889

KEYWORD

nonn,hard,more

AUTHOR

Ivan Panchenko, Feb 15 2014

STATUS

approved

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Last modified May 13 11:49 EDT 2021. Contains 343839 sequences. (Running on oeis4.)