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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A106822 Triangle read by rows: g.f. for row n is Product( (x^i-x^(r+1))/(1-x^i), i = 1..r-2). 2
1, 1, 0, 1, 1, 1, 0, 0, 0, 1, 1, 2, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 3, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 3, 3, 2, 2, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,12

REFERENCES

See A008967 for references.

LINKS

Table of n, a(n) for n=0..104.

EXAMPLE

Initial rows are:

[1]

[1]

[0, 1, 1, 1]

[0, 0, 0, 1, 1, 2, 1, 1]

[0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 2, 1, 1]

[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 2, 2, 1, 1]

MAPLE

f2:=r->mul( (x^i-x^(r+1))/(1-x^i), i = 1..r-2); for r from 1 to 10 do series(f2(r), x, 50); od:

CROSSREFS

If the initial zeros in each row are omitted, we get A008967.

Cf. A008967, A106823.

Sequence in context: A053622 A016408 A316868 * A203905 A309142 A064532

Adjacent sequences:  A106819 A106820 A106821 * A106823 A106824 A106825

KEYWORD

nonn,tabf

AUTHOR

N. J. A. Sloane, May 20 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 October 18 12:18 EDT 2019. Contains 328160 sequences. (Running on oeis4.)