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Search: a047859 -id:a047859
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Triangle read by rows: T(n,k)=k*binomial(n-1,k-1)+binomial(n-1,k) (1<=k<=n).
+10
1
1, 2, 2, 3, 5, 3, 4, 9, 10, 4, 5, 14, 22, 17, 5, 6, 20, 40, 45, 26, 6, 7, 27, 65, 95, 81, 37, 7, 8, 35, 98, 175, 196, 133, 50, 8, 9, 44, 140, 294, 406, 364, 204, 65, 9, 10, 54, 192, 462, 756, 840, 624, 297, 82, 10, 11, 65, 255, 690, 1302, 1722, 1590, 1005, 415, 101, 11, 12, 77
OFFSET
1,2
COMMENTS
Triangle is P*M, where P is Pascal's triangle as an infinite lower triangular matrix and M is the infinite bidiagonal matrix with (1,2,3...) in the main diagonal and (1,1,1...) in the subdiagonal.
EXAMPLE
First few rows of the triangle are:
1;
2, 2;
3, 5, 3;
4, 9, 10, 4;
5, 14, 22, 17, 5;
6, 20, 40, 45, 26, 6
...
MAPLE
T:=(n, k)->k*binomial(n-1, k-1)+binomial(n-1, k): for n from 1 to 12 do seq(T(n, k), k=1..n) od; # yields sequence in triangular form
MATHEMATICA
Flatten[Table[k Binomial[n-1, k-1]+Binomial[n-1, k], {n, 20}, {k, n}]] (* Harvey P. Dale, Jan 28 2012 *)
CROSSREFS
Row sums = A047859: (1, 4, 11, 27, 143, 319...) A124726 is generated in an analogous manner by taking M*P instead of P*M.
KEYWORD
nonn,tabl
AUTHOR
EXTENSIONS
Edited by N. J. A. Sloane, Nov 24 2006
STATUS
approved
Triangle by rows, derived from the beheaded Pascal's triangle, A074909.
+10
1
1, 0, 2, 0, 1, 3, 0, 1, 3, 4, 0, 1, 4, 6, 5, 0, 1, 5, 10, 10, 6, 0, 1, 6, 15, 20, 15, 7, 0, 1, 7, 21, 35, 35, 21, 8, 0, 1, 8, 28, 56, 70, 56, 28, 9, 0, 1, 9, 36, 84, 126, 126, 84, 36, 10, 0, 1, 10, 45, 120, 210, 252, 210, 120, 45, 11
OFFSET
0,3
COMMENTS
Row sums of the triangle = 2^n.
Let the triangle = an infinite lower triangular matrix, M. Then M * The Bernoulli numbers, A027641/A027642 as a vector V = [1, -1, 0, 0, 0,...]. M * the Bernoulli sequence variant starting [1, 1/2, 1/6,...] = [1, 1, 1,...]. M * 2^n: [1, 2, 4, 8,...] = A027649. M * 3^n = A255463; while M * [1, 2, 3,...] = A047859, and M * A027649 = A027650.
Row sums of powers of the triangle generate the Poly-Bernoulli number sequences shown in the array of A099594. - Gary W. Adamson, Mar 21 2012
Triangle T(n,k) given by (0, 1/2, 1/2, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (2, -1/2, 1/2, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938. - Philippe Deléham, Mar 25 2012
REFERENCES
Konrad Knopp, Elements of the Theory of Functions, Dover, 1952,pp 117-118.
FORMULA
Partial differences of the beheaded Pascal's triangle A074909 starting from the top, by columns.
G.f.: (1-x)/(1-x-2*y*x+y*x^2+y^2*x^2). - Philippe Deléham, Mar 25 2012
T(n,k) = T(n-1,k) + 2*T(n-1,k-1) - T(n-2,k-1) - T(n-2,k-2), T(0,0) = T(2,1) = 1, T(1,0) = T(2,0) = 0, T(1,1) = 2, T(2,2) = 3 and T(n,k) = 0 if k<0 or if k>n. - Philippe Deléham, Mar 25 2012
EXAMPLE
{1},
{0, 2},
{0, 1, 3},
{0, 1, 3, 4},
{0, 1, 4, 6, 5},
{0, 1, 5, 10, 10, 6},
{0, 1, 6, 15, 20, 15, 7},
{0, 1, 7, 21, 35, 35, 21, 8},
{0, 1, 8, 28, 56, 70, 56, 28, 9},
{0, 1, 9, 36, 84, 126, 126, 84, 36, 10},
{0, 1, 10, 45, 120, 210, 252, 210, 120, 45, 11}
...
MATHEMATICA
t2[n_, m_] = If[m - 1 <= n, Binomial[n, m - 1], 0];
O2 = Table[Table[If[n == m, t2[n, m] + 1, t2[n, m]], {m, 0, n}], {n, 0, 10}];
Flatten[O2]
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
STATUS
approved
1, 3, 1, 6, 4, 1, 11, 10, 5, 1, 20, 21, 15, 6, 1, 37, 41, 36, 21, 7, 1, 70, 78, 77, 57, 28, 8, 1, 135, 148, 155, 134, 85, 36, 9, 1, 264, 283, 303, 289, 219, 121, 45, 10, 1, 521, 547, 586, 592, 508, 340, 166, 55, 11, 1
OFFSET
0,2
COMMENTS
Left column = A006127: (1, 3, 6, 11, 20, 37,...). Row sums = A047859: (1, 4, 11, 27, 63,...).
FORMULA
(A007318 * A000012) + (A000012 * A007318) - A007318 as infinite lower triangular matrices.
EXAMPLE
First few rows of the triangle are:
1;
3, 1;
6, 4, 1;
11, 10, 5, 1;
20, 21, 15, 6, 1;
37, 41, 36, 21, 7, 1;
...
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, Jul 08 2007
STATUS
approved

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