login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 59th year, we have over 358,000 sequences, and we’ve crossed 10,300 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A221866 Maximum value achievable for n X n version of Le Monde grid problem, using the original rules. 1
1, 4, 57, 2473, 349712 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

From Christian Boyer, Apr 18 2013: (Start)

The beginning of this version of the game is different from that in A224784: now we start with 1's in two cells (not necessarily adjacent). After that the rules are the same: each new chosen cell is filled with the sum of the neighboring cells.

With these rules, the new maximum for 3 X 3 is no longer 44, but 57:

1 2 1

3 7 30

10 20 57

a(1) is no longer defined, but we set it equal to 1. a(2) and a(4) are the same as in A224784, but a(5)-a(8) are different. (End)

REFERENCES

Eric Angelini and others, A Grid With MAX, Postings to the Math Fun Mailing List, April 14, 2013 onwards.

Christian Boyer, A Grid With MAX, Postings to the Math Fun Mailing List, April 18-25, 2013.

LINKS

Table of n, a(n) for n=1..5.

Le Monde, Les défis mathématiques du "Monde", épisode 3 : la grille de sommes

EXAMPLE

From Christian Boyer, Apr 25 2013: (Start)

a(5) = 349712: 1 7 11 33 33

2 4 22 99 165

1 30272 16581 286 550

97477 67204 13662 2508 836

349712 185031 6688 4180 836

a(6) >= 150941453:

1 7 11 33 99 99

2 4 22 66 297 495

1 14105024 49432840 150941453 858 1650

4574593 9530402 25797322 75705032 5016 2508

2859120 1715472 381216 65208 22572 7524

571824 571824 190608 125400 37620 7524

a(7) >= 164912612349.

a(8) >= 639561837115046.

(End)

CROSSREFS

Cf. A224784.

Sequence in context: A231491 A240887 A209316 * A270881 A246618 A103907

Adjacent sequences: A221863 A221864 A221865 * A221867 A221868 A221869

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane, Apr 18 2013

EXTENSIONS

Value of a(5) and lower bounds for a(6)-a(8) corrected by Christian Boyer, Apr 25 2013

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 2 15:00 EST 2022. Contains 358510 sequences. (Running on oeis4.)