A056243 -id:A056243 - cp's OEIS frontend

A117317 Triangle related to partitions of n.

1, 2, 1, 4, 5, 1, 8, 16, 9, 1, 16, 44, 41, 14, 1, 32, 112, 146, 85, 20, 1, 64, 272, 456, 377, 155, 27, 1, 128, 640, 1312, 1408, 833, 259, 35, 1, 256, 1472, 3568, 4712, 3649, 1652, 406, 44, 1, 512, 3328, 9312, 14608, 14002, 8361, 3024, 606, 54, 1, 1024, 7424, 23552

Offset: 0

Paul Barry, Mar 07 2006

Row sums are A007052. Diagonal sums are A052988. Reversal of A056242.

Essentially given by (0, 2, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (1, 0, 1/2, 1/2, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938. - Philippe Deléham, Jan 28 2012

			Triangle begins
1,
2, 1,
4, 5, 1,
8, 16, 9, 1,
16, 44, 41, 14, 1,
32, 112, 146, 85, 20, 1,
64, 272, 456, 377, 155, 27, 1
Triangle (0, 2, 0, 0, 0, 0, ...) DELTA (1, 0, 1/2, 1/2, 0, 0, ...) begins :
1
0, 1
0, 2, 1
0, 4, 5, 1
0, 8, 16, 9, 1
0, 16, 44, 41, 14, 1
0, 32, 112, 146, 85, 20, 1
0, 64, 272, 456, 377, 155, 27, 1

Reinhard Zumkeller, Rows n = 0..125 of table, flattened

Cf. Columns : A000079, A053220, A056243 ; Diagonals : A000012, A000096

a117317 n k = a117317_tabl !! n !! k
a117317_row n = a117317_tabl !! n
a117317_tabl = map reverse a056242_tabl
-- Reinhard Zumkeller, May 08 2014

Number triangle T(n,k)=sum{j=0..n-k, C(n+j,k)C(n-k,j)}
T(n,k) = 2*T(n-1,k) + 2*T(n-1,k-1) - T(n-2,k-1) - T(n-2,k-2) for n>1. - Philippe Deléham, Jan 28 2012
G.f.: (1-y*x)/(1-2*(y+1)*x+y*(y+1)*x^2). - Philippe Deléham, Jan 28 2012

A185342 Triangle of successive recurrences in columns of A117317(n).

Original entry on oeis.org

2, 4, -4, 6, -12, 8, 8, -24, 32, -16, 10, -40, 80, -80, 32, 12, -60, 160, -240, 192, -64, 14, -84, 280, -560, 672, -448, 128, 16, -112, 448, -1120, 1792, -1792, 1024, -256, 18, -144, 672, -2016, 4032, -5376, 4608, -2304, 512, 20, -180, 960, -3360, 8064

Offset: 0

Paul Curtz, Jan 26 2012

A117317 (A):
1
2    1
4    5   1
8   16   9   1
16  44  41  14   1
32 112 146  85  20  1
64 272 456 377 155 27 1
have for their columns successive signatures
(2) (4,-4) (6,-12,8) (8,-24, 32, -16) (10,-40,80,-80,32) i.e. a(n).
Take based on abs(A133156) (B):
1
2   0
4   1  0
8   4  0 0
16 12  1 0 0
32 32  6 0 0 0
64 80 24 1 0 0 0.
The recurrences of successive columns are also a(n). a(n) columns: A005843(n+1), A046092(n+1), A130809, A130810, A130811, A130812, A130813.
A053220 + A001787 = A014480.

			Triangle T(n,k),for 1<=k<=n, begins :
2                                         (1)
4    -4                                   (2)
6   -12   8                               (3)
8   -24  32   -16                         (4)
10  -40  80   -80   32                    (5)
12  -60 160  -240  192   -64              (6)
14  -84 280  -560  672  -448  128         (7)
16 -112 448 -1120 1792 -1792 1024 -256    (8)
Successive rows can be divided by A171977.

G. C. Greubel, Table of n, a(n) for the first 100 rows, flattened

Cf. For (A): A053220, A056243. For (B): A000079, A001787, A001788, A001789. For A193862: A115068 (a Coxeter group). For (2): A014480 (also (3),(4),(5),..); also A053220 and A001787.

Cf. A007318.

Table[(-1)*Binomial[n, k]*(-2)^k, {n, 1, 20}, {k, 1, n}] // Flatten (* G. C. Greubel, Jun 27 2017 *)

for(n=1,20, for(k=1,n, print1((-2)^(k+1)*binomial(n,k)/2, ", "))) \\ G. C. Greubel, Jun 27 2017

Take A133156(n) without 1's or -1's double triangle (C)=
2
4
8      -4
16    -12
32    -32   6
64    -80  24
128  -192  80   -8
256  -448 240  -40
512 -1024 672 -160 10;
a(n) is increasing odd diagonals and increasing (sign changed) even diagonals. Rows sum of (C) = A201629 (?) Another link between Chebyshev polynomials and cos( ).
Absolute values: A013609(n) without 1's. Also 2*A193862 = (2*A002260)*A135278.
T(n,k) = T(n-1,k) - 2*T(n-1,k-1) for k>1, T(n,1) = 2*n = 2*T(n-1,1) - T(n-2,1). - Philippe Deléham, Feb 11 2012
T(n,k) = (-1)* Binomial(n,k)*(-2)^k, 1<=k<=n. - Philippe Deléham, Feb 11 2012

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A117317 Triangle related to partitions of n.

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