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Number of slanted 5Xn (i=1..5)X(j=i..n+i-1) 1..4 arrays with all 1s connected, all 2s connected, all 3s connected, all 4s connected, 1 in the upper left corner, 2 in the upper right corner, 3 in the lower left corner, 4 in the lower right corner, and with no element having more than 3 neighbors with the same value
(history; published version)

#3 by Russ Cox at Sat Mar 31 12:35:35 EDT 2012

AUTHOR

_R. H. Hardin (rhhardin(AT)att.net) _ Sep 17 2009

Discussion

Sat Mar 31

12:35

OEIS Server: https://oeis.org/edit/global/875

#2 by N. J. A. Sloane at Sat Oct 02 03:00:00 EDT 2010

KEYWORD

nonn,new

nonn

AUTHOR

Ron R. H. Hardin (rhhardin(AT)att.net) Sep 17 2009

#1 by N. J. A. Sloane at Tue Jun 01 03:00:00 EDT 2010

NAME

Number of slanted 5Xn (i=1..5)X(j=i..n+i-1) 1..4 arrays with all 1s connected, all 2s connected, all 3s connected, all 4s connected, 1 in the upper left corner, 2 in the upper right corner, 3 in the lower left corner, 4 in the lower right corner, and with no element having more than 3 neighbors with the same value

DATA

7, 40, 2467, 18900, 174197, 1357468, 9996371, 68364692, 445699471, 2796474838, 16994094852

OFFSET

2,1

EXAMPLE

Some solutions for n=3

...1.1.2...........1.1.2...........1.1.2...........1.1.2........

.....1.2.2...........1.1.1...........1.2.2...........1.1.1......

.......2.2.2...........1.1.1...........2.3.3...........1.1.1....

.........4.4.4...........3.3.3...........3.3.4...........3.3.4..

...........3.4.4...........3.3.4...........3.4.4...........3.4.4

------

...1.1.2...........1.2.2...........1.2.2...........1.1.2........

.....1.1.1...........2.2.2...........2.2.2...........1.2.2......

.......1.4.4...........3.3.3...........4.4.4...........3.3.3....

.........4.4.4...........3.3.4...........4.4.4...........3.3.4..

...........3.4.4...........3.4.4...........3.4.4...........3.4.4

------

...1.1.2...........1.1.2...........1.1.2...........1.2.2........

.....1.2.2...........1.2.4...........1.1.4...........2.2.4......

.......2.2.3...........2.4.4...........1.4.4...........2.4.4....

.........3.3.4...........4.4.4...........4.4.4...........4.4.4..

...........3.4.4...........3.4.4...........3.4.4...........3.4.4

KEYWORD

nonn

AUTHOR

Ron Hardin (rhhardin(AT)att.net) Sep 17 2009

STATUS

approved