A097281 - OEIS

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A097281

Integer part of the area of integer triangle [A001611(n), A001611(n+1), A001611(n+2)].

0, 1, 2, 5, 9, 18, 35, 71, 144, 294, 601, 1231, 2526, 5191, 10672, 21950, 45159, 92920, 191214, 393512, 809864, 1666775, 3430425, 7060297, 14531166, 29907455, 61554442, 126689294, 260747884, 536663296, 1104544280, 2273340315 (list; graph; refs; listen; history; internal format)

	OFFSET	`0,3`
	FORMULA	`a(n) = floor(SquareRoot(s(n) * (s(n)-A001611(n)) * (s(n)-A001611(n+1)) * (s(n)-A001611(n+2)))), where s(n) is the semiperimeter: s(n)=A097280(n)/2.`
	CROSSREFS	`Sequence in context: A077865 A117353 A103422 * A068036 A077947 A077972` `Adjacent sequences: A097278 A097279 A097280 * A097282 A097283 A097284`
	KEYWORD	`nonn`
	AUTHOR	`Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Aug 04 2004`

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Last modified February 16 08:09 EST 2012. Contains 205888 sequences.