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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A243820 Number of Dyck paths of semilength n such that all sixteen consecutive step patterns of length 4 occur at least once. 8
38, 587, 4785, 31398, 190050, 1043248, 5324534, 25711105, 119092876, 533680433, 2329450085, 9955122396, 41824314441, 173289259905, 709861015186, 2880803895035, 11601285215222, 46422795985447, 184784743066842, 732324944072523, 2891815190097065, 11385122145001833 (list; graph; refs; listen; history; text; internal format)
OFFSET

10,1

LINKS

Alois P. Heinz, Table of n, a(n) for n = 10..70

EXAMPLE

a(10) = 38: 10101100111101000010, 10101101001111000010, 10101111000011010010, 10101111001101000010, 10101111010000110010, 10101111010011000010, 10110011110100001010, 10110011110101000010, 10110100111100001010, 10110101001111000010, 10111100001101001010, 10111100001101010010, 10111100110100001010, 10111100110101000010, 10111101000011001010, 10111101001100001010, 10111101010000110010, 10111101010011000010, 11001011110000110100, 11001011110100001100, 11001101011110000100, 11001101111000010100, 11001111000010110100, 11001111010000101100, 11001111010110000100, 11001111011000010100, 11010010111100001100, 11010011110000101100, 11010110011110000100, 11010111100001001100, 11010111100001100100, 11010111100100001100, 11010111100110000100, 11011001111000010100, 11011110000101001100, 11011110000110010100, 11011110010100001100, 11011110011000010100.  Here 1=Up=(1,1), 0=Down=(1,-1).

MAPLE

b:= proc(x, y, t, s) option remember; `if`(y<0 or y>x, 0,

      `if`(x=0, `if`(s={}, 1, 0), `if`(nops(s)>x, 0, add(

      b(x-1, y-1+2*j, irem(2*t+j, 8), s minus {2*t+j}), j=0..1))))

    end:

a:= n-> add(b(2*n-3, l[], {$0..15}), l=[[1, 5], [1, 6], [3, 7]]):

seq(a(n), n=10..20);

CROSSREFS

Cf. A242257, A243882, A243965, A243966.

Sequence in context: A160317 A088891 A159784 * A268765 A202715 A094034

Adjacent sequences:  A243817 A243818 A243819 * A243821 A243822 A243823

KEYWORD

nonn

AUTHOR

Alois P. Heinz, Jun 11 2014

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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 20 13:59 EDT 2018. Contains 316379 sequences. (Running on oeis4.)