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A130125
Triangle defined by A128174 * A130123, read by rows.
5
1, 0, 2, 1, 0, 4, 0, 2, 0, 8, 1, 0, 4, 0, 16, 0, 2, 0, 8, 0, 32, 1, 0, 4, 0, 16, 0, 64, 0, 2, 0, 8, 0, 32, 0, 128, 1, 0, 4, 0, 16, 0, 64, 0, 256, 0, 2, 0, 8, 0, 32, 0, 128, 0, 512, 1, 0, 4, 0, 16, 0, 64, 0, 256, 0, 1024, 0, 2, 0, 8, 0, 32, 0, 128, 0, 512, 0, 2048
OFFSET
0,3
COMMENTS
Row sums = A000975: (1, 2, 5, 10, 21, 42, ...).
FORMULA
A128174 * A130123 as infinite lower triangular matrices. By columns, (2^k, 0, 2^k, 0, ...).
T(n,k) = 2^(k-1)*(1 + (-1)^(n-k)). - G. C. Greubel, Jun 05 2019
EXAMPLE
First few rows of the triangle are:
1;
0, 2;
1, 0, 4;
0, 2, 0, 8;
1, 0, 4, 0, 16;
0, 2, 0, 8, 0, 32; ...
MATHEMATICA
Table[2^(k-1)*(1+(-1)^(n-k)), {n, 0, 10}, {k, 0, n}]//Flatten (* G. C. Greubel, Jun 05 2019 *)
PROG
(PARI) {T(n, k) = 2^(k-1)*(1+(-1)^(n-k))}; \\ G. C. Greubel, Jun 05 2019
(Magma) [[2^(k-1)*(1+(-1)^(n-k)): k in [0..n]]: n in [0..10]]; // G. C. Greubel, Jun 05 2019
(Sage) [[2^(k-1)*(1+(-1)^(n-k)) for k in (0..n)] for n in (0..10)] # G. C. Greubel, Jun 05 2019
(GAP) Flat(List([0..10], n-> List([0..n], k-> 2^(k-1)*(1+(-1)^(n-k)) ))); # G. C. Greubel, Jun 05 2019
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, May 11 2007
EXTENSIONS
More terms added by G. C. Greubel, Jun 05 2019
STATUS
approved