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A110555
Triangle of partial sums of alternating binomial coefficients: T(n, k) = Sum_{j=0..k} binomial(n, j)*(-1)^j, for n >= 0, 0 <= k <= n.
21
1, 1, 0, 1, -1, 0, 1, -2, 1, 0, 1, -3, 3, -1, 0, 1, -4, 6, -4, 1, 0, 1, -5, 10, -10, 5, -1, 0, 1, -6, 15, -20, 15, -6, 1, 0, 1, -7, 21, -35, 35, -21, 7, -1, 0, 1, -8, 28, -56, 70, -56, 28, -8, 1, 0, 1, -9, 36, -84, 126, -126, 84, -36, 9, -1, 0, 1, -10, 45, -120, 210, -252, 210, -120
OFFSET
0,8
LINKS
FORMULA
T(n, 0) = 1, T(n, n) = 0^n, T(n, k) = -T(n-1, k-1) + T(n-1, k), for 0 < k < n.
T(n, k) = binomial(n-1, k)*(-1)^k, 0 <= k < n, T(n, n) = 0^n.
T(n, n-k-1) = -T(n, k), for 0 < k < n.
T(n, k) = A071919(n, k)*(-1)^k and A071919(n, k) = abs(T(n, k)).
Triangle T(n,k), 0 <= k <= n, read by rows, given by [1, 0, 0, 0, 0, 0, 0, 0, ...] DELTA [0, -1, 0, 0, 0, 0, 0, 0, ...] where DELTA is the operator defined in A084938. - Philippe Deléham, Sep 05 2005
G.f.: (1 + x*y) / (1 + x*y - x). - R. J. Mathar, Aug 11 2015
EXAMPLE
Triangle T(n, k) starts:
[0] 1;
[1] 1, 0;
[2] 1, -1, 0;
[3] 1, -2, 1, 0;
[4] 1, -3, 3, -1, 0;
[5] 1, -4, 6, -4, 1, 0;
[6] 1, -5, 10, -10, 5, -1, 0;
[7] 1, -6, 15, -20, 15, -6, 1, 0;
[8] 1, -7, 21, -35, 35, -21, 7, -1, 0.
MAPLE
T := (n, k) -> (-1)^k * binomial(n-1, k):
seq(print(seq(T(n, k), k = 0..n)), n = 0..7); # Peter Luschny, Apr 13 2023
MATHEMATICA
T[0, 0] := 1; T[n_, n_] := 0; T[n_, k_] := (-1)^k*Binomial[n - 1, k]; Table[T[n, k], {n, 0, 20}, {k, 0, n}] // Flatten (* G. C. Greubel, Aug 31 2017 *)
PROG
(PARI) concat(1, for(n=1, 10, for(k=0, n, print1(if(k != n, (-1)^k*binomial(n-1, k), 0), ", ")))) \\ G. C. Greubel, Aug 31 2017
CROSSREFS
T(n,1) = -n + 1 for n>0;
T(n,2) = A000217(n-2) for n > 1;
T(n,3) = -A000292(n-4) for n > 2;
T(n,4) = A000332(n-1) for n > 3;
T(n,5) = -A000389(n-1) for n > 5;
T(n,6) = A000579(n-1) for n > 6;
T(n,7) = -A000580(n-1) for n > 7;
T(n,8) = A000581(n-1) for n > 8;
T(n,9) = -A000582(n-1) for n > 9;
T(n,10) = A001287(n-1) for n > 10;
T(n,11) = -A001288(n-1) for n > 11;
T(n,12) = A010965(n-1) for n > 12;
T(n,13) = -A010966(n-1) for n > 13;
T(n,14) = A010967(n-1) for n > 14;
T(n,15) = -A010968(n-1) for n > 15;
T(n,16) = A010969(n-1) for n > 16.
Cf. A071919 (variant), A000007 (row sums), A110556 (central terms).
Sequence in context: A213889 A363779 A373164 * A097805 A071919 A321791
KEYWORD
sign,easy,tabl
AUTHOR
Reinhard Zumkeller, Jul 27 2005
EXTENSIONS
Typo in name corrected by Andrey Zabolotskiy, Feb 22 2022
Offset corrected by Peter Luschny, Apr 13 2023
STATUS
approved