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!)
A185907 Weight array of A185908, by descending antidiagonals. 4

%I #24 Jul 31 2023 16:26:03

%S 1,0,1,0,1,1,0,0,0,1,0,0,1,0,1,0,0,0,0,0,1,0,0,0,1,0,0,1,0,0,0,0,0,0,

%T 0,1,0,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,1,0,0,

%U 0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1

%N Weight array of A185908, by descending antidiagonals.

%C A member of the accumulation chain ... < A185907 < A185908 < A185909 < ...

%C (See A144112 for definitions of weight array and accumulation array.)

%C Omitting the first row and reading the remaining array by descending antidiagonals results in A115356. - _Georg Fischer_, Jul 26 2023

%H G. C. Greubel, <a href="/A185907/b185907.txt">Table of n, a(n) for the first 50 rows, flattened</a>

%F All entries in column 1 and main diagonal are 1, all others are 0.

%e Northwest corner:

%e 1, 0, 0, 0, 0, 0, 0, 0

%e 1, 1, 0, 0, 0, 0, 0, 0

%e 1, 0, 1, 0, 0, 0, 0, 0

%e 1, 0, 0, 1, 0, 0, 0, 0

%e 1, 0, 0, 0, 1, 0, 0, 0

%t (* This program generates the array A185908, then its accumulation array, A185909, and then its weight array, A185907. *)

%t f[n_,0]:=0;f[0,k_]:=0; (* needed for the weight array *)

%t f[n_,k_]:=Min[n,k]+n-1;

%t TableForm[Table[f[n,k],{n,1,10},{k,1,15}]]

%t Table[f[n-k+1,k],{n,14},{k,n,1,-1}]//Flatten

%t s[n_,k_]:=Sum[f[i,j],{i,1,n},{j,1,k}]; (* accumulation array of {f(n,k)} *)

%t TableForm[Table[s[n,k],{n,1,10},{k,1,15}] (* A185909 *)]

%t Table[s[n-k+1,k],{n,14},{k,n,1,-1}]//Flatten

%t w[m_,n_]:=f[m,n]+f[m-1,n-1]-f[m,n-1]-f[m-1,n]/;Or[m>0,n>0];

%t TableForm[Table[w[n,k],{n,1,10},{k,1,15}]] (* A185907 *)

%t Table[w[n-k+1,k],{n,16},{k,n,1,-1}]//Flatten

%Y Cf. A115356, A144112, A185908, A185909.

%K nonn,tabl

%O 1

%A _Clark Kimberling_, Feb 06 2011

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 April 19 17:39 EDT 2024. Contains 371797 sequences. (Running on oeis4.)