id:A115256 - OEIS Search Results

Search: id:A115256

Displaying 1-1 of 1 results found.

page 1

Diagonal sums of correlation triangle of central binomial coefficients.

+0
2

1, 2, 8, 25, 90, 312, 1145, 4186, 15640, 58681, 222298, 845848, 3235385, 12418650, 47827992, 184688185, 714884186, 2772776984, 10774163001, 41932100698, 163430680600, 637793652281, 2491918144602, 9746480252952, 38157725306425 (list; graph; listen)

	OFFSET	`0,2`
	COMMENT	`Diagonal sums of number triangle A115255.`
	FORMULA	`G.f.: 1/(sqrt(1-4x)sqrt(1-4x^2)(1-x^3)); a(n)=sum{k=0..floor(n/2), sum{j=0..n-k, [j<=k]C(2k-2j, k-j)[j<=n-2k]C(2n-4k-2j, n-2k-j)}}.`
	CROSSREFS	`Sequence in context: A037560 A138804 A036367 this_sequence A132963 A122404 A102942` `Adjacent sequences: A115253 A115254 A115255 this_sequence A115257 A115258 A115259`
	KEYWORD	`easy,nonn`
	AUTHOR	`Paul Barry (pbarry(AT)wit.ie), Jan 18 2006`

page 1

Search completed in 0.002 seconds

Last modified November 18 20:14 EST 2008. Contains 147244 sequences.

AT&T Labs Research