A130790 - OEIS

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A130790

Number of nodes in the Lucas-Pratt primality tree rooted at prime(n).

0, 1, 1, 2, 2, 2, 1, 2, 3, 3, 3, 2, 2, 4, 4, 3, 4, 3, 4, 4, 2, 4, 3, 3, 2, 2, 3, 4, 2, 3, 4, 4, 2, 5, 3, 3, 4, 2, 4, 5, 4, 3, 4, 2, 3, 4, 5, 4, 4, 4, 4, 4, 3, 2, 1, 5, 5, 3, 5, 4, 6, 3, 3, 5, 4, 5, 5, 4, 6, 5, 3, 5, 5, 5, 4, 5, 3, 4, 2, 3, 5, 5, 6, 2, 4, 4, 3, 4, 5, 6, 5, 5, 2, 4, 5, 3, 5, 4, 5, 3 (list; graph; refs; listen; history; internal format)

	OFFSET	`1,4`
	COMMENTS	`The primality tree starts at an odd prime at the root node. The branches of each node are the odd primes that divide the value of (the node minus 1). The length of the longest branch is related to A126805. Following the branch with the largest label gives A083647.`
	LINKS	`J. Bayless, The Lucas-Pratt primality tree, Math. Comp. vol 77 (2008) 495-502.`
	CROSSREFS	`Sequence in context: A083647 A056691 A205011 * A179647 A029330 A132225` `Adjacent sequences: A130787 A130788 A130789 * A130791 A130792 A130793`
	KEYWORD	`easy,nonn`
	AUTHOR	`R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jul 15 2007, Mar 07 2008`

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Last modified February 14 23:53 EST 2012. Contains 205689 sequences.