0,2

A113355 equals the matrix square of A113350, where column 2 of A113350^2 = column 0 of A113350^6.

(PARI) {a(n)=local(A, B); A=matrix(1, 1); A[1, 1]=1; for(m=2, n+3, B=matrix(m, m); for(i=1, m, for(j=1, i, if(i<3|j==i|j>m-1, B[i, j]=1, if(j==1, B[i, 1]=1, B[i, j]=(A^(2*j-1))[i-j+1, 1])); )); A=B); (matrix(#A, #A, r, c, if(r>=c, (A^(2*c))[r-c+1, 1]))^2)[n+3, 3]}

Cf. A113340, A113350, A113355, A113356 (column 0), A113357 (column 1), A113359 (column 3).

Sequence in context: A068768 A053507 A060917 this_sequence A015611 A127650 A103759

Adjacent sequences: A113355 A113356 A113357 this_sequence A113359 A113360 A113361

nonn

Paul D. Hanna (pauldhanna(AT)juno.com), Nov 08 2005