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A136521 Triangle read by rows: (1, 2, 2, 2, ...) on the main diagonal and the rest zeros. 3

%I #12 May 04 2021 02:02:25

%S 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,

%T 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,

%U 0,0,0,0,0,0,0,0,0,2,0,0,0,0,0,0,0,0,0,0,0,0,2

%N Triangle read by rows: (1, 2, 2, 2, ...) on the main diagonal and the rest zeros.

%H G. C. Greubel, <a href="/A136521/b136521.txt">Rows n = 0..25 of the triangle, flattened</a>

%F By columns, (1, 0, 0, 0, ...) in leftmost column; all others are (2, 0, 0, 0, ...).

%F By rows, row 1 = 1, others = (n-1) zeros followed by "2".

%F A007318(n,k) * T(n,k) = A124927(n,k).

%F T(n,k) * A007318(n,k) = A134058(n,k).

%F A001263(n,k) * T(n,k) = A136522(n,k).

%F From _G. C. Greubel_, May 03 2021: (Start)

%F T(n, k) = 2*[k=n] - [n=0].

%F Sum_{k=0..n} T(n, k) = A040000(n). (End)

%e First few rows of the triangle are:

%e 1;

%e 0, 2;

%e 0, 0, 2;

%e 0, 0, 0, 2;

%e 0, 0, 0, 0, 2;

%e ...

%t Table[2*Boole[k==n] -Boole[n==0], {n,0,12}, {k,0,n}]//Flatten (* _G. C. Greubel_, May 03 2021 *)

%o (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

%Y Cf. A001263, A007318, A040000, A124927, A134058, A136522.

%K nonn,tabl,less,easy

%O 0,3

%A _Gary W. Adamson_, Jan 02 2008

%E More terms added by _G. C. Greubel_, May 03 2021

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Last modified April 18 04:31 EDT 2024. Contains 371767 sequences. (Running on oeis4.)