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

 

Logo

The submissions stack has been unacceptably high for several months now. Please voluntarily restrict your submissions and please help with the editing. (We don't want to have to impose further limits.)

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A213057 Triangle read by rows: left edge is all 1's, right edge is 1, 2, 3, 4, ...; construct an internal entriy by concatenating the two entries above it. 1
1, 1, 2, 1, 12, 3, 1, 112, 123, 4, 1, 1112, 112123, 1234, 5, 1, 11112, 1112112123, 1121231234, 12345, 6, 1, 111112, 111121112112123, 11121121231121231234, 112123123412345, 123456, 7, 1, 1111112, 111112111121112112123, 11112111211212311121121231121231234, 11121121231121231234112123123412345, 112123123412345123456, 1234567, 8 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Closely related to A004073 - see Kubo-Vakil.

After the 9th row of course we will encounter strings like 111...110, which is unsatisfactory. Still, the initial rows look nice and the sequence serves as a pointer to the Kubo-Vakil paper.

REFERENCES

T. Kubo and R. Vakil, On Conway's recursive sequence, Discr. Math. 152 (1996), 225-252.

LINKS

Table of n, a(n) for n=0..35.

EXAMPLE

Triangle begins

1

1 2

1 12 3

1 112 123 4

1 1112 112123 1234 5

1 11112 1112112123 1121231234 12345 6

1 111112 111121112112123 11121121231121231234 112123123412345 123456 7

...

CROSSREFS

Cf. A004073, A007318.

Sequence in context: A249163 A211099 A058734 * A103187 A107722 A167128

Adjacent sequences:  A213054 A213055 A213056 * A213058 A213059 A213060

KEYWORD

nonn,tabl

AUTHOR

N. J. A. Sloane, Jun 03 2012

STATUS

approved

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

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

Last modified August 27 15:19 EDT 2015. Contains 261092 sequences.