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

 

Logo

Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing.
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A143211 Triangle read by rows, T(n,k) = F(n)*F(k); 1<=k<=n. 2
1, 1, 1, 2, 2, 4, 3, 3, 6, 9, 5, 5, 10, 15, 25, 8, 8, 16, 24, 40, 64, 13, 13, 26, 39, 65, 104, 169, 21, 21, 42, 63, 105, 168, 273, 441, 34, 34, 68, 102, 170, 272, 442, 714, 1156, 55, 55, 110, 165, 275, 440, 715, 1155, 1870, 3025, 89, 89, 178, 267, 445, 712, 1157, 1869 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

Left border = Fibonacci numbers, A000045.

Right border = F(n)^2, A007598.

Row sums = A143212: (1, 2, 8, 21, 60, 160, 429,...).

LINKS

Table of n, a(n) for n=1..63.

FORMULA

Triangle read by rows, T(n,k) = F(n)*F(k), 1<=k<=n; = A127647 * A000012 * A127647, as infinite lower triangular matrices.

EXAMPLE

First few rows of the triangle =

1;

1, 1;

2, 2, 4;

3, 3, 6, 9;

5, 5, 10, 15, 25;

8, 8, 16, 24, 40, 64;

13, 13, 26, 39, 65, 104, 169;

21, 21, 42, 63, 105, 168, 273, 441;

...

Example: T(8,7) = 273 = 21*13

CROSSREFS

Cf. A000045, A007598, A127647, A143212.

Sequence in context: A205678 A128590 A143228 * A209755 A131052 A209138

Adjacent sequences:  A143208 A143209 A143210 * A143212 A143213 A143214

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson, Jul 30 2008

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 December 12 15:11 EST 2019. Contains 329960 sequences. (Running on oeis4.)