login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A026536 Triangular array T read by rows: T(i,0)=T(i,2i)=1 for i >= 0, T(i,1)=T(i,2i-1)=[ i/2 ] for i >= 1, for even n >= 2, T(i,j)=T(i-1,j-2)+T(i-1,j-1)+T(i-1,j) for 2<=j<=2i-2, for odd n >= 3, T(i,j)=T(i-1,j-2)+T(i-1,j) for 2<=j<=2i-2. 20
1, 1, 0, 1, 1, 1, 2, 1, 1, 1, 1, 3, 2, 3, 1, 1, 1, 2, 5, 6, 8, 6, 5, 2, 1, 1, 2, 6, 8, 13, 12, 13, 8, 6, 2, 1, 1, 3, 9, 16, 27, 33, 38, 33, 27, 16, 9, 3, 1, 1, 3, 10, 19, 36, 49, 65, 66, 65, 49, 36, 19, 10, 3, 1, 1, 4, 14, 32, 65, 104, 150, 180, 196, 180 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,7

LINKS

Table of n, a(n) for n=1..74.

FORMULA

T(n, k) = number of integer strings s(0), ..., s(n) such that s(0)=0, s(n)=n-k, |s(i)-s(i-1)|<=1 if i is even, |s(i)-s(i-1)|=1 if i is odd.

CROSSREFS

Cf. A026527.

Sequence in context: A063420 A029385 A185155 * A046213 A215625 A181386

Adjacent sequences:  A026533 A026534 A026535 * A026537 A026538 A026539

KEYWORD

nonn,tabl

AUTHOR

Clark Kimberling

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

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

Last modified May 24 13:46 EDT 2013. Contains 225621 sequences.