login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A113126 A simple 4-diagonal matrix. 3
1, 1, 2, 1, 2, 3, 1, 2, 3, 4, 0, 2, 3, 4, 5, 0, 0, 3, 4, 5, 6, 0, 0, 0, 4, 5, 6, 7, 0, 0, 0, 0, 5, 6, 7, 8, 0, 0, 0, 0, 0, 6, 7, 8, 9, 0, 0, 0, 0, 0, 0, 7, 8, 9, 10, 0, 0, 0, 0, 0, 0, 0, 8, 9, 10, 11, 0, 0, 0, 0, 0, 0, 0, 0, 9, 10, 11, 12, 0, 0, 0, 0, 0, 0, 0, 0, 0, 10, 11, 12, 13, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Row sums are A113127. Diagonal sums are A109613. Diagonals are A000027.

LINKS

Table of n, a(n) for n=0..100.

FORMULA

Number triangle where column k has g.f. (1+x+x^2+x^3)(k+1)x^k.

EXAMPLE

Triangle begins

1;

1,2;

1,2,3;

1,2,3,4;

0,2,3,4,5;

0,0,3,4,5,6;

0,0,0,4,5,6,7;

0,0,0,0,5,6,7,8;

0,0,0,0,0,6,7,8,9;

CROSSREFS

Cf. A113125.

Sequence in context: A115452 A039676 A242359 * A138060 A023121 A136261

Adjacent sequences:  A113123 A113124 A113125 * A113127 A113128 A113129

KEYWORD

easy,nonn,tabl

AUTHOR

Paul Barry, Oct 14 2005

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 April 18 03:14 EDT 2021. Contains 343072 sequences. (Running on oeis4.)