login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 56th year, we are closing in on 350,000 sequences, and we’ve crossed 9,700 citations (which often say “discovered thanks to the OEIS”).

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A047030 Array T read by diagonals: T(h,k)=number of paths consisting of steps from (0,0) to (h,k) such that each step has length 1 directed up or right and no step touches the line y=x/4 unless x=0 or x=h. 8
1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 3, 3, 1, 1, 1, 4, 6, 4, 2, 1, 1, 5, 10, 10, 4, 1, 1, 1, 6, 15, 20, 14, 4, 2, 1, 1, 7, 21, 35, 34, 18, 4, 3, 1, 1, 8, 28, 56, 69, 52, 22, 4, 4, 1, 1, 9, 36, 84, 125, 121, 74, 26, 8, 5, 1, 1, 10, 45, 120, 209, 246, 195, 100 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,8

LINKS

Table of n, a(n) for n=0..73.

M. Janjic and B. Petkovic, A Counting Function, arXiv preprint arXiv:1301.4550, 2013. - From N. J. A. Sloane, Feb 13 2013

M. Janjic, B. Petkovic, A Counting Function Generalizing Binomial Coefficients and Some Other Classes of Integers, J. Int. Seq. 17 (2014) # 14.3.5

EXAMPLE

Diagonals (beginning on row 0): {1}; {1,1}; {1,1,1}; {1,2,1,1}; ...

CROSSREFS

Sequence in context: A135225 A208891 A177767 * A047120 A096751 A293551

Adjacent sequences:  A047027 A047028 A047029 * A047031 A047032 A047033

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 | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 2 04:43 EST 2021. Contains 349437 sequences. (Running on oeis4.)