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A122496
T(n, m) = 2^m * binomial(-m, n), for 0 <= m <= n, n >= 0, triangle read by rows.
1
1, 0, -2, 0, 2, 12, 0, -2, -16, -80, 0, 2, 20, 120, 560, 0, -2, -24, -168, -896, -4032, 0, 2, 28, 224, 1344, 6720, 29568, 0, -2, -32, -288, -1920, -10560, -50688, -219648, 0, 2, 36, 360, 2640, 15840, 82368, 384384, 1647360, 0, -2, -40, -440, -3520, -22880, -128128, -640640, -2928640, -12446720
OFFSET
1,3
FORMULA
T(n, m) = 2^m * binomial(-m, n), for 0 <= m <= n, n >= 0. - G. C. Greubel, May 15 2019
EXAMPLE
Triangle begins as:
1;
0, -2;
0, 2, 12;
0, -2, -16, -80;
0, 2, 20, 120, 560;
0, -2, -24, -168, -896, -4032;
MATHEMATICA
f[i_, k_, l_]:= Binomial[k-l, i-Min[k, l]]/2^(k-l);
Table[f[i, 0, l], {i, 0, 12}, {l, 0, i}] // Flatten (* modified by G. C. Greubel, May 15 2019 *)
PROG
(Magma) [[2^m*Binomial(-m, n): m in [0..n]]: n in [0..12]]; // G. C. Greubel, May 15 2019
(Sage) [[2^m*binomial(-m, n) for m in (0..n)] for n in (0..12)] # G. C. Greubel, May 15 2019
(GAP) Flat(List([0..12], n-> List([0..n], k-> 2^k*Binomial(-k, n) ))); # G. C. Greubel, May 15 2019
CROSSREFS
Sequence in context: A211910 A250406 A107094 * A335756 A230813 A367074
KEYWORD
sign,easy,tabl
AUTHOR
Roger L. Bagula, Sep 14 2006
EXTENSIONS
Edited by N. J. A. Sloane, Oct 01 2006
Edited by G. C. Greubel, May 15 2019
Better name using formula given, Joerg Arndt, Jan 21 2024
STATUS
approved