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

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A158793 Triangle read by rows: product of A130595 and A092392 considered as infinite lower triangular arrays. 3
1, 1, 1, 3, 1, 1, 7, 4, 1, 1, 19, 9, 5, 1, 1, 51, 26, 11, 6, 1, 1, 141, 70, 34, 13, 7, 1, 1, 393, 197, 92, 43, 15, 8, 1, 1, 1107, 553, 265, 117, 53, 17, 9, 1, 1, 3139, 1570, 751, 346, 145, 64, 19, 10, 1, 1, 8953, 4476, 2156, 991, 441, 176, 76, 21, 11, 1, 1 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,4

COMMENTS

Riordan array (f(x), x*g(x)) where f(x) is the g.f. of A002426 and where g(x) is the g.f. of A005043. [From Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Dec 05 2009]

FORMULA

T(n,m) = sum_{k=m..n-1} A130595(n,k) * A092392(k+1,m+1), with the triangular interpretation of A092392.

Row sums: sum_{m=0..n-1} T(n,m) = A005773(n).

T(n,0) = A002426(n).

Conjecture: T(n,1) = A113682(n-1). [R. J. Mathar, Oct 06 2009]

Sum-{k, 0<=k<=n} T(n,k)*x^k = A002426(n), A005773(n+1), A000244(n), A126932(n) for x = 0,1,2,3 respectively. [From Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Dec 03 2009]

EXAMPLE

The first rows of the triangle are:

1;

1, 1;

3, 1, 1;

7, 4, 1, 1;

19, 9, 5, 1, 1;

51, 26, 11, 6, 1, 1;

141, 70, 34, 13, 7, 1, 1;

393, 197, 92, 43, 15, 8, 1, 1;

1107, 553, 265, 117, 53, 17, 9, 1, 1;

3139, 1570, 751, 346, 145, 64, 19, 10, 1, 1;

8953, 4476, 2156, 991, 441, 176, 76, 21, 11, 1, 1;

CROSSREFS

Cf. A046899, A007318.

Sequence in context: A121300 A128119 A158198 * A112996 A136621 A108625

Adjacent sequences:  A158790 A158791 A158792 * A158794 A158795 A158796

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson & Roger L. Bagula (qntmpkt(AT)yahoo.com), Mar 26 2009

EXTENSIONS

Simplified definition - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Oct 06 2009

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 17 16:32 EST 2012. Contains 206050 sequences.