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A130127
Triangle defined by A000012 * A130125, read by rows.
2
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, 12, 24, 32, 64, 64, 128, 5, 8, 16, 24, 48, 64, 128, 128, 256, 5, 10, 16, 32, 48, 96, 128, 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
OFFSET
1,3
COMMENTS
Row sums = A011377: (1, 3, 8, 18, 39, ...). A130126 = A130125 * A000012.
FORMULA
T(n,k) = 2^(k-1) * floor((n-k+2)/2). - G. C. Greubel, Jun 06 2019
EXAMPLE
First few rows of the triangle:
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;
...
MATHEMATICA
Table[2^(k-1)*Floor[(n-k+2)/2], {n, 1, 12}, {k, 1, n}]//Flatten (* G. C. Greubel, Jun 06 2019 *)
PROG
(PARI) {T(n, k) = 2^(k-1)*floor((n-k+2)/2)}; \\ G. C. Greubel, Jun 06 2019
(Magma) [[2^(k-1)*Floor((n-k+2)/2): k in [1..n]]: n in [1..12]]; // G. C. Greubel, Jun 06 2019
(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
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, May 11 2007
EXTENSIONS
More terms added by G. C. Greubel, Jun 06 2019
STATUS
approved