A213853 Rectangular array: (row n) = b**c, where b(h) = h, c(h) = binomial(2*n-4+2*h,n-2+h), n>=1, h>=1, and ** = convolution.
1, 4, 2, 13, 10, 6, 42, 38, 32, 20, 141, 136, 128, 110, 70, 492, 486, 476, 452, 392, 252, 1767, 1760, 1748, 1718, 1638, 1428, 924, 6474, 6466, 6452, 6416, 6316, 6036, 5280, 3432, 24051, 24042, 24026, 23984, 23864, 23514, 22506, 19734, 12870
Offset: 1
Examples
Northwest corner (the array is read by falling antidiagonals): 1 4 13 42 141 2 10 38 136 486 6 32 128 476 1748 20 110 452 1718 6416 70 392 1638 6316 23864
Links
- Clark Kimberling, Antidiagonals n = 1..60, flattened
Crossrefs
Cf. A213500.
Programs
-
Mathematica
b[n_]:=n;c[n_]:=Binomial[2n-2,n-1] t[n_,k_]:=Sum[b[k-i]c[n+i],{i,0,k-1}] TableForm[Table[t[n,k],{n,1,10},{k,1,10}]] Flatten[Table[t[n-k+1,k],{n,12},{k,n,1,-1}]] r[n_]:=Table[t[n,k],{k,1,20}] (* A213853 *)
Comments