0,8

Triangle T begins:

1;

1, 1;

1, 1, 1;

1, 2, 1, 1;

1, 3, 3, 1, 1;

1, 5, 6, 4, 1, 1;

1, 9, 13, 10, 5, 1, 1;

1, 18, 30, 26, 15, 6, 1, 1;

1, 40, 76, 71, 45, 21, 7, 1, 1;

1, 98, 211, 210, 140, 71, 28, 8, 1, 1;

1, 263, 638, 673, 466, 246, 105, 36, 9, 1, 1;

1, 769, 2088, 2328, 1665, 902, 399, 148, 45, 10, 1, 1; ...

Matrix square T^2 begins:

1;

2, 1;

3, 2, 1;

5, 5, 2, 1;

9, 11, 7, 2, 1;

18, 27, 19, 9, 2, 1;

40, 71, 57, 29, 11, 2, 1;

98, 202, 180, 101, 41, 13, 2, 1; ...

where column 0 of T^2 equals column 1 of T (shifted).

Matrix cube T^3 begins:

1;

3, 1;

6, 3, 1;

13, 9, 3, 1;

30, 25, 12, 3, 1;

76, 75, 40, 15, 3, 1;

211, 238, 144, 58, 18, 3, 1; ...

where column 0 of T^3 equals column 2 of T (shifted).

Matrix power T^4 begins:

1;

4, 1;

10, 4, 1;

26, 14, 4, 1;

71, 46, 18, 4, 1;

210, 159, 70, 22, 4, 1; ...

where column 0 of T^4 equals column 3 of T (shifted).

(PARI) {T(n, k)=local(M=matrix(n+1, n+1)); for(r=1, n+1, for(c=1, r, M[r, c]=if(r==c|c==1, 1, if(c>1, (M^c)[r-c+0, 1])))); return(M[n+1, k+1])}

Columns: A130581, A130582, A130583.

Sequence in context: A096751 A099233 A133815 this_sequence A110541 A079115 A072906

Adjacent sequences: A130577 A130578 A130579 this_sequence A130581 A130582 A130583

nonn,tabl

Paul D. Hanna (pauldhanna(AT)juno.com), Jun 05 2007