A127749 - OEIS

This site is supported by donations to The OEIS Foundation.

A127749

Inverse of number triangle A(n,k)=if(k<=n,if(n<=2k,1/(2n+1),0),0).

1, 0, 3, 0, -3, 5, 0, 3, -5, 7, 0, 0, 0, -7, 9, 0, -3, 5, 0, -9, 11, 0, 0, 0, 0, 0, -11, 13, 0, 3, -5, 7, 0, 0, -13, 15, 0, 0, 0, 0, 0, 0, 0, -15, 17, 0, 0, 0, -7, 9, 0, 0, 0, -17, 19, 0, 0, 0, 0, 0, 0, 0, 0, 0, -19, 21, 0, -3, 5 (list; table; graph; refs; listen; history; internal format)

	OFFSET	`0,3`
	COMMENTS	`Conjectures: row sums modulo 2 are the Fredholm-Rueppel sequence A036987; row sums of triangle modulo 2 are A111982. Row sums are A127750.`
	EXAMPLE	`Triangle begins` `1,` `0, 3,` `0, -3, 5,` `0, 3, -5, 7,` `0, 0, 0, -7, 9,` `0, -3, 5, 0, -9, 11,` `0, 0, 0, 0, 0, -11, 13,` `0, 3, -5, 7, 0, 0, -13, 15,` `0, 0, 0, 0, 0, 0, 0, -15, 17,` `0, 0, 0, -7, 9, 0, 0, 0, -17, 19,` `0, 0, 0, 0, 0, 0, 0, 0, 0, -19, 21,` `0, -3, 5, 0, -9, 11, 0, 0, 0, 0, -21, 23,` `0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -23, 25` `Inverse of triangle` `1,` `0, 1/3,` `0, 1/5, 1/5,` `0, 0, 1/7, 1/7,` `0, 0, 1/9, 1/9, 1/9,` `0, 0, 0, 1/11, 1/11, 1/11,` `0, 0, 0, 1/13, 1/13, 1/13, 1/13,` `0, 0, 0, 0, 1/15, 1/15, 1/15, 1/15,` `0, 0, 0, 0, 1/17, 1/17, 1/17, 1/17, 1/17,` `0, 0, 0, 0, 0, 1/19, 1/19, 1/19, 1/19, 1/19,` `0, 0, 0, 0, 0, 1/21, 1/21, 1/21, 1/21, 1/21, 1/21`
	CROSSREFS	`Cf. A111967.` `Sequence in context: A073367 A111862 A060858 * A198431 A138188 A014715` `Adjacent sequences: A127746 A127747 A127748 * A127750 A127751 A127752`
	KEYWORD	`sign,tabl`
	AUTHOR	`Paul Barry (pbarry(AT)wit.ie), Jan 28 2007`

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

Last modified February 17 23:58 EST 2012. Contains 206085 sequences.