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 A056844 Number of polydiamonds: polyominoes made from n diamonds. 2
 1, 2, 9, 40, 238, 1517 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Comment from Larry_Reeves(AT)intranetsolutions.com, Jun 22 2001: If you look at Vicher's picture of the 40 4-celled polydiamonds (link in A056844), near the middle of the picture is a polydiamond that looks like the traditional 2-D representation of a cube with an extra diamond stuck to the edge. Depending on how you orient the cube, there are actually 2 different ways to form this polydiamond, although there is no change in the perimeter shape. I haven't confirmed that this explains the difference in values for sizes 5 and above for A056844 and A056845, but it looks like a possible explanation. LINKS M. Vicher, Polyforms M. Vicher, The 40 4-celled polydiamonds M. Vicher, The 40 4-celled polydiamonds CROSSREFS Cf. A056845. Sequence in context: A261047 A052846 A293152 * A220471 A213095 A238372 Adjacent sequences:  A056841 A056842 A056843 * A056845 A056846 A056847 KEYWORD nice,nonn,more AUTHOR James A. Sellers, Aug 28 2000 EXTENSIONS Edited by N. J. A. Sloane, Jun 21, 2001 STATUS approved

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Last modified October 19 05:08 EDT 2018. Contains 316336 sequences. (Running on oeis4.)