OFFSET
0,2
COMMENTS
FORMULA
T(n,k) = Sum_{j=0..k} 3^j*2^(n-j). - Detlef Meya, Dec 20 2023
T(n,k) = 2^n*(3*(3/2)^k-2). - Alois P. Heinz, Dec 20 2023
EXAMPLE
The start of the sequence as a triangle read by rows:
1;
2, 5;
4, 10, 19;
8, 20, 38, 65;
16, 40, 76, 130, 211;
32, 80, 152, 260, 422, 665;
...
MATHEMATICA
T[n_, k_]:=Sum[3^j*2^(n-j), {j, 0, k}]; Flatten[Table[T[n, k], {n, 0, 8}, {k, 0, n}]] (* Detlef Meya, Dec 20 2023 *)
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Christopher Tompkins, Nov 18 2013
STATUS
approved