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!)
A113711 Triangle, read by rows, where row n forms a polynomial in y=2*k that generates diagonal n as k=0,1,2,... for n>=0; thus T(n,k) = Sum_{j=0..n-k} T(n-k,j)*(2*k)^j, with T(n,0)=T(n,n)=1. 6

%I #5 Jun 13 2017 23:36:16

%S 1,1,1,1,3,1,1,11,5,1,1,51,29,7,1,1,291,189,55,9,1,1,1955,1373,463,89,

%T 11,1,1,14947,11037,4159,921,131,13,1,1,127203,97565,39871,9945,1611,

%U 181,15,1,1,1188067,942109,408703,112217,20411,2581,239,17,1

%N Triangle, read by rows, where row n forms a polynomial in y=2*k that generates diagonal n as k=0,1,2,... for n>=0; thus T(n,k) = Sum_{j=0..n-k} T(n-k,j)*(2*k)^j, with T(n,0)=T(n,n)=1.

%e Triangle begins:

%e 1;

%e 1,1;

%e 1,3,1;

%e 1,11,5,1;

%e 1,51,29,7,1;

%e 1,291,189,55,9,1;

%e 1,1955,1373,463,89,11,1;

%e 1,14947,11037,4159,921,131,13,1;

%e 1,127203,97565,39871,9945,1611,181,15,1;

%e 1,1188067,942109,408703,112217,20411,2581,239,17,1; ...

%e where diagonals are generated by row polynomials:

%e T(6,5) = (1) + (1)*(2*5) = 11.

%e T(6,4) = (1) + (3)*(2*4) + (1)*(2*4)^2 = 89.

%e T(6,3) = (1) + (11)*(2*3) + (5)*(2*3)^2 + (1)*(2*3)^3 = 463.

%e T(6,2) = (1) + (51)*(2*2) + (29)*(2*2)^2 + (7)*(2*2)^3 + (1)*(2*2)^4 = 1373.

%o (PARI) T(n,k)=if(n<k || k<0,0,if(n==k || k==0,1,sum(j=0,n-k,T(n-k,j)*(2*k)^j)))

%Y Cf. A091150, A113716, A113712 (column 1), A113713 (column 2), A113714 (column 3), A113715 (row sums).

%K nonn,tabl

%O 0,5

%A _Paul D. Hanna_, Nov 08 2005

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 July 22 16:15 EDT 2024. Contains 374540 sequences. (Running on oeis4.)