A012264 - OEIS

This site is supported by donations to The OEIS Foundation.

A012264

Number of real roots of x - x^3/3! + x^5/5! - ... + (-1)^n*x^(2n+1)/(2n+1)!.

1, 3, 1, 3, 5, 3, 5, 7, 5, 7, 5, 7, 9, 7, 9, 7, 9, 11, 9, 11, 13, 11, 13, 11, 13, 15, 13, 15, 17, 15, 17, 15, 17, 19, 17, 19, 17, 19, 21, 19, 21, 23, 21, 23, 21, 23, 25, 23, 25, 23, 25, 27, 25, 27, 29, 27, 29, 27, 29, 31, 29, 31, 33 (list; graph; refs; listen; history; internal format)

	OFFSET	`0,2`
	REFERENCES	`Jim Propp (propp(AT)math.wisc.edu), posting to math-fun mailing list May 30 1997.`
	MAPLE	`Digits := 25: t1 := 0: for k from 1 by 2 to 51 do t1 := t1+(-1)^( (k-1)/2 )x^k/k!; print(nops([ fsolve(t1k!) ])); od:`
	CROSSREFS	`Cf. A012265.` `Sequence in context: A126637 A110091 A005474 * A063198 A122582 A173039` `Adjacent sequences: A012261 A012262 A012263 * A012265 A012266 A012267`
	KEYWORD	`nonn,nice`
	AUTHOR	`N. J. A. Sloane (njas(AT)research.att.com).`
	EXTENSIONS	`More terms from James A. Sellers (sellersj(AT)math.psu.edu)`

Content is available under The OEIS End-User License Agreement .

Last modified February 15 23:53 EST 2012. Contains 205860 sequences.