A121782 - OEIS

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A121782

Series expansion for mean-squared radius of gyration of rectangles on square lattice.

0, 8, 66, 288, 900, 2280, 4998, 9856, 17928, 30600, 49610, 77088, 115596, 168168, 238350, 330240, 448528, 598536, 786258, 1018400, 1302420, 1646568, 2059926, 2552448, 3135000, 3819400, 4618458, 5546016, 6616988, 7847400 (list; graph; refs; listen; history; text; internal format)

	OFFSET	`1,2`
	LINKS	`I. Jensen, Table of n, a(n) for n = 1..55 (from link below)` `I. Jensen, Series expansions for self-avoiding polygons`
	FORMULA	`All terms appear to be generated by n^2(n-1)(n^2+2)/3. - T. D. Noe, Feb 09 2007` `Conjectures from Colin Barker, Apr 17 2017: (Start)` `G.f.: 2x^2(1 + x)^2(4 + x) / (1 - x)^6.` `a(n) = 6a(n-1) - 15a(n-2) + 20a(n-3) - 15a(n-4) + 6a(n-5) - a(n-6) for n>6.` `(End)`
	CROSSREFS	`Sequence in context: A230736 A008893 A168302 * A212784 A121781 A121780` `Adjacent sequences: A121779 A121780 A121781 * A121783 A121784 A121785`
	KEYWORD	`nonn`
	AUTHOR	`N. J. A. Sloane, Aug 30 2006`
	STATUS	`approved`

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Last modified January 18 10:35 EST 2021. Contains 340254 sequences. (Running on oeis4.)