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A136521
Triangle read by rows: (1, 2, 2, 2, ...) on the main diagonal and the rest zeros.
3
1, 0, 2, 0, 0, 2, 0, 0, 0, 2, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2
OFFSET
0,3
FORMULA
By columns, (1, 0, 0, 0, ...) in leftmost column; all others are (2, 0, 0, 0, ...).
By rows, row 1 = 1, others = (n-1) zeros followed by "2".
A007318(n,k) * T(n,k) = A124927(n,k).
T(n,k) * A007318(n,k) = A134058(n,k).
A001263(n,k) * T(n,k) = A136522(n,k).
From G. C. Greubel, May 03 2021: (Start)
T(n, k) = 2*[k=n] - [n=0].
Sum_{k=0..n} T(n, k) = A040000(n). (End)
EXAMPLE
First few rows of the triangle are:
1;
0, 2;
0, 0, 2;
0, 0, 0, 2;
0, 0, 0, 0, 2;
...
MATHEMATICA
Table[2*Boole[k==n] -Boole[n==0], {n, 0, 12}, {k, 0, n}]//Flatten (* G. C. Greubel, May 03 2021 *)
PROG
(Sage) flatten([[2*bool(k==n) -bool(n==0) for k in (0..n)] for n in (0..12)]) # G. C. Greubel, May 03 2021
CROSSREFS
KEYWORD
nonn,tabl,less,easy
AUTHOR
Gary W. Adamson, Jan 02 2008
EXTENSIONS
More terms added by G. C. Greubel, May 03 2021
STATUS
approved