login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A171661 Triangle T(n,k) (n >= 0, 0 <= k <= n) read by rows: T(n,0) = T(n,1) = A000984(n); for n >= 2 and k >= 2, T(n,k) = T(n,k-1) - T(n-1,k-2). 1

%I #4 Nov 03 2016 07:28:52

%S 1,2,2,6,6,4,20,20,14,8,70,70,50,30,16,252,252,182,112,62,32,924,924,

%T 672,420,238,126,64,3432,3432,2508,1584,912,492,254,128,12870,12870,

%U 9438,6006,3498,1914,1002,510,256,48620,48620,35750,22880,13442,7436

%N Triangle T(n,k) (n >= 0, 0 <= k <= n) read by rows: T(n,0) = T(n,1) = A000984(n); for n >= 2 and k >= 2, T(n,k) = T(n,k-1) - T(n-1,k-2).

%e Triangle starts:

%e 1

%e 2,2

%e 6,6,4

%e 20,20,14,8

%e 70,70,50,30,16

%Y Cf. A000984, A172021.

%K nonn,tabl

%O 0,2

%A _Mark Dols_, Dec 14 2009

%E Edited by _N. J. A. Sloane_, Jan 24 2010

%E More terms from _Mark Dols_, Jan 24 2010

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 1 05:26 EST 2024. Contains 370430 sequences. (Running on oeis4.)