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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

%I #42 Apr 13 2023 06:44:28

%S 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,

%T -6,15,-20,15,-6,1,0,1,-7,21,-35,35,-21,7,-1,0,1,-8,28,-56,70,-56,28,

%U -8,1,0,1,-9,36,-84,126,-126,84,-36,9,-1,0,1,-10,45,-120,210,-252,210,-120

%N 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.

%H G. C. Greubel, <a href="/A110555/b110555.txt">Table of n, a(n) for the first 50 rows, flattened</a>

%H Ângela Mestre and José Agapito, <a href="https://www.emis.de/journals/JIS/VOL22/Agapito/mestre8.html">A Family of Riordan Group Automorphisms</a>, J. Int. Seq., Vol. 22 (2019), Article 19.8.5.

%H <a href="/index/Pas#Pascal">Index entries for triangles and arrays related to Pascal's triangle</a>

%F 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.

%F T(n, k) = binomial(n-1, k)*(-1)^k, 0 <= k < n, T(n, n) = 0^n.

%F T(n, n-k-1) = -T(n, k), for 0 < k < n.

%F T(n, k) = A071919(n, k)*(-1)^k and A071919(n, k) = abs(T(n, k)).

%F 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

%F G.f.: (1 + x*y) / (1 + x*y - x). - _R. J. Mathar_, Aug 11 2015

%e Triangle T(n, k) starts:

%e [0] 1;

%e [1] 1, 0;

%e [2] 1, -1, 0;

%e [3] 1, -2, 1, 0;

%e [4] 1, -3, 3, -1, 0;

%e [5] 1, -4, 6, -4, 1, 0;

%e [6] 1, -5, 10, -10, 5, -1, 0;

%e [7] 1, -6, 15, -20, 15, -6, 1, 0;

%e [8] 1, -7, 21, -35, 35, -21, 7, -1, 0.

%p T := (n, k) -> (-1)^k * binomial(n-1, k):

%p seq(print(seq(T(n, k), k = 0..n)), n = 0..7); # _Peter Luschny_, Apr 13 2023

%t 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 *)

%o (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

%Y T(n,1) = -n + 1 for n>0;

%Y T(n,2) = A000217(n-2) for n > 1;

%Y T(n,3) = -A000292(n-4) for n > 2;

%Y T(n,4) = A000332(n-1) for n > 3;

%Y T(n,5) = -A000389(n-1) for n > 5;

%Y T(n,6) = A000579(n-1) for n > 6;

%Y T(n,7) = -A000580(n-1) for n > 7;

%Y T(n,8) = A000581(n-1) for n > 8;

%Y T(n,9) = -A000582(n-1) for n > 9;

%Y T(n,10) = A001287(n-1) for n > 10;

%Y T(n,11) = -A001288(n-1) for n > 11;

%Y T(n,12) = A010965(n-1) for n > 12;

%Y T(n,13) = -A010966(n-1) for n > 13;

%Y T(n,14) = A010967(n-1) for n > 14;

%Y T(n,15) = -A010968(n-1) for n > 15;

%Y T(n,16) = A010969(n-1) for n > 16.

%Y Cf. A071919 (variant), A000007 (row sums), A110556 (central terms).

%Y Cf. A008949, A007318.

%K sign,easy,tabl

%O 0,8

%A _Reinhard Zumkeller_, Jul 27 2005

%E Typo in name corrected by _Andrey Zabolotskiy_, Feb 22 2022

%E Offset corrected by _Peter Luschny_, Apr 13 2023

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Last modified April 24 09:18 EDT 2024. Contains 371935 sequences. (Running on oeis4.)