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A151523
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Number of 1-sided strip polyrhombs with n cells.
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4
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1, 2, 4, 10, 20, 48, 106, 252, 578, 1372, 3208, 7584, 17850, 42102, 99276, 233716, 550960, 1295146, 3050226, 7161346, 16846668, 39511876, 92845830
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| Also counts 1-sided strip polyrects.
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LINKS
| Ed Pegg, Jr., Illustrations of polyforms
Eric Weisstein's World of Mathematics, Polyrhomb
Eric Weisstein's World of Mathematics, Polyrect
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CROSSREFS
| Strip polyominoes by group of symmetries relating shapes considered the same: A002013 (all symmetries), A182644 (translations only), A151514 (rotations and translations), A151527 (horizontal and vertical reflections, rotations of order 2 and translations), A151524 (reflections in either diagonal, rotations of order 2 and translations), A151523 (rotations of order 2 and translations), A151526 (reflections in a horizontal line and translations), A182646 (reflections in a NE-SW diagonal line and translations)
Sequence in context: A121880 A094536 A003407 * A026395 A090246 A104442
Adjacent sequences: A151520 A151521 A151522 * A151524 A151525 A151526
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KEYWORD
| nonn
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AUTHOR
| Ed Pegg, Jr., (ed(AT)mathpuzzle.com), May 13 2009
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EXTENSIONS
| Edited and a(15)-a(23) by Joseph Myers (jsm(AT)polyomino.org.uk), Nov 24 2010
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