login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A176021 Triangle T(n, k) = 1 - (-1)^n*(n! + 1) + A176013(n, k) + A176013(n, n-k+1) read by rows. 2

%I #12 Feb 08 2021 05:17:41

%S 1,1,1,1,-10,1,1,72,72,1,1,-528,-678,-528,1,1,4770,6780,6780,4770,1,1,

%T -48025,-87568,-68458,-87568,-48025,1,1,524384,1287776,947520,947520,

%U 1287776,524384,1,1,-6169282,-19982590,-18010942,-10305790,-18010942,-19982590,-6169282,1

%N Triangle T(n, k) = 1 - (-1)^n*(n! + 1) + A176013(n, k) + A176013(n, n-k+1) read by rows.

%C Row sums are: 1, 2, -8, 146, -1732, 23102, -339642, 5519362, -98631416, 1926628022, ...

%H G. C. Greubel, <a href="/A176021/b176021.txt">Rows n = 1..100 of the triangle, flattened</a>

%F T(n, k) = 1 - (-1)^n*(n! + 1) + A176013(n, k) + A176013(n, n-k+1).

%F T(n, k) = 1 - (-1)^n*(n! + 1) + binomial(n+1, k)*( A008297(n, k) + A008297(n, n-k+1) )/(n+1). - _G. C. Greubel_, Feb 08 2021

%e Triangle begins as:

%e 1;

%e 1, 1;

%e 1, -10, 1;

%e 1, 72, 72, 1;

%e 1, -528, -678, -528, 1;

%e 1, 4770, 6780, 6780, 4770, 1;

%e 1, -48025, -87568, -68458, -87568, -48025, 1;

%e 1, 524384, 1287776, 947520, 947520, 1287776, 524384, 1;

%e 1, -6169282, -19982590, -18010942, -10305790, -18010942, -19982590, -6169282, 1;

%t A176013[n_, k_]:= (-1)^n*(n!/(k*k!))*Binomial[n-1, k-1]*Binomial[n, k-1];

%t T[n_, m_]:= 1 - (-1)^n*(n! + 1) + A176013[n, k] + A176013[n, n-k+1];

%t Table[T[n, k], {n, 12}, {k, n}]//Flatten

%o (Sage)

%o def A176013(n, k): return (-1)^n*(factorial(n)/(k*factorial(k)))*binomial(n-1, k-1)*binomial(n, k-1)

%o flatten([[1 - (-1)^n*(factorial(n) + 1) + A176013(n, k) + A176013(n, n-k+1) for k in (1..n)] for n in (1..12)]) # _G. C. Greubel_, Feb 08 2021

%o (Magma)

%o A176013:= func< n,k | (-1)^n*(Factorial(n)/(k*Factorial(k)))*Binomial(n-1, k-1)*Binomial(n, k-1) >;

%o [1 - (-1)^n*(Factorial(n) + 1) + A176013(n, k) + A176013(n, n-k+1) : k in [1..n], n in [1..12]]; // _G. C. Greubel_, Feb 08 2021

%Y Cf. A008297, A176013, A176022.

%K sign,tabl,easy,less

%O 1,5

%A _Roger L. Bagula_, Apr 06 2010

%E Edited by _G. C. Greubel_, Feb 08 2021

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 23 08:33 EDT 2024. Contains 371905 sequences. (Running on oeis4.)