login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A118045 Triangle T, read by rows, equal to a diagonal bisection of A118032 such that diagonal n of T equals diagonal 2n+1 of A118032: T(n,k) = A118032(2n+1-k,k); also equals the matrix product of A118032 and SHIFT_UP(A118032). 17
1, 3, 2, 9, 8, 3, 26, 28, 15, 4, 73, 86, 57, 24, 5, 191, 250, 192, 96, 35, 6, 500, 696, 567, 356, 145, 48, 7, 1234, 1824, 1683, 1060, 590, 204, 63, 8, 3051, 4754, 4392, 3344, 1765, 906, 273, 80, 9, 7201, 11562, 12084, 8672, 5895, 2718, 1316, 352, 99, 10, 16995 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..55.

EXAMPLE

Triangle begins:

1;

3, 2;

9, 8, 3;

26, 28, 15, 4;

73, 86, 57, 24, 5;

191, 250, 192, 96, 35, 6;

500, 696, 567, 356, 145, 48, 7;

1234, 1824, 1683, 1060, 590, 204, 63, 8;

3051, 4754, 4392, 3344, 1765, 906, 273, 80, 9;

7201, 11562, 12084, 8672, 5895, 2718, 1316, 352, 99, 10; ...

which is formed from the odd-indexed diagonals of triangle

A118032, which starts:

1;

1, 1;

2, 2, 1;

3, 4, 3, 1;

6, 8, 6, 4, 1;

9, 14, 15, 8, 5, 1; ...

Let U = SHIFT_UP(A118032), shifting columns of A118032 up 1 row

and dropping the main diagonal, so that U =

1;

2, 2;

3, 4, 3;

6, 8, 6, 4;

9, 14, 15, 8, 5;

16, 28, 24, 24, 10, 6; ...

Then the matrix product A118032*U equals this triangle.

CROSSREFS

. columns: A118046, A118047, A118048; A118049 (row sums); related triangles: A118032, A118040.

Sequence in context: A124003 A159588 A321572 * A276023 A268822 A201926

Adjacent sequences:  A118042 A118043 A118044 * A118046 A118047 A118048

KEYWORD

nonn,tabl

AUTHOR

Paul D. Hanna, Apr 10 2006

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified September 19 04:39 EDT 2019. Contains 327187 sequences. (Running on oeis4.)