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A130127 Triangle defined by A000012 * A130125, read by rows. 2

%I

%S 1,1,2,2,2,4,2,4,4,8,3,4,8,8,16,3,6,8,16,16,32,4,6,12,16,32,32,64,4,8,

%T 12,24,32,64,64,128,5,8,16,24,48,64,128,128,256,5,10,16,32,48,96,128,

%U 256,256,512,6,10,20,32,64,96,192,256,512,512,1024,6,12,20,40,64,128,192,384,512,1024,1024,2048

%N Triangle defined by A000012 * A130125, read by rows.

%C Row sums = A011377: (1, 3, 8, 18, 39, ...). A130126 = A130125 * A000012.

%H G. C. Greubel, <a href="/A130127/b130127.txt">Rows n = 1..100 of triangle, flattened</a>

%F T(n,k) = 2^(k-1) * floor((n-k+2)/2). - _G. C. Greubel_, Jun 06 2019

%e First few rows of the triangle:

%e 1;

%e 1, 2;

%e 2, 2, 4;

%e 2, 4, 4, 8;

%e 3, 4, 8, 8, 16;

%e 3, 6, 8, 16, 16, 32;

%e 4, 6, 12, 16, 32, 32, 64;

%e ...

%t Table[2^(k-1)*Floor[(n-k+2)/2], {n,1,12}, {k,1,n}]//Flatten (* _G. C. Greubel_, Jun 06 2019 *)

%o (PARI) {T(n,k) = 2^(k-1)*floor((n-k+2)/2)}; \\ _G. C. Greubel_, Jun 06 2019

%o (Magma) [[2^(k-1)*Floor((n-k+2)/2): k in [1..n]]: n in [1..12]]; // _G. C. Greubel_, Jun 06 2019

%o (Sage) [[2^(k-1)*floor((n-k+2)/2) for k in (1..n)] for n in (1..12)] # _G. C. Greubel_, Jun 06 2019

%Y Cf. A000012, A130125, A130126, A011377.

%K nonn,tabl

%O 1,3

%A _Gary W. Adamson_, May 11 2007

%E More terms added by _G. C. Greubel_, Jun 06 2019

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Last modified January 30 12:56 EST 2023. Contains 359945 sequences. (Running on oeis4.)