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 A165380 Number of slanted n X n (i=1..n)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 0
 1, 40, 1012, 18900, 598332, 30346872, 3445935988 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,2 LINKS EXAMPLE Some solutions for n=4 ...1.1.1.2.........1.2.2.2.........1.1.1.2.........1.1.4.2...... .....2.2.2.4.........2.2.2.2.........1.1.2.2.........4.4.2.4.... .......2.3.4.4.........3.3.2.4.........1.1.2.4.........4.4.4.4.. .........3.4.4.4.........3.3.4.4.........3.2.4.4.........3.3.4.4 ------ ...1.2.2.2.........1.2.2.2.........1.1.2.2.........1.1.1.2...... .....3.3.2.2.........3.3.2.4.........2.2.2.2.........2.2.2.2.... .......3.3.2.2.........3.3.4.4.........3.3.2.2.........3.3.3.4.. .........3.2.2.4.........3.3.4.4.........3.3.4.4.........3.3.4.4 ------ ...1.1.1.2.........1.1.2.2.........1.1.1.2.........1.1.2.2...... .....1.1.2.2.........1.1.3.3.........2.2.2.2.........1.2.2.2.... .......3.3.3.4.........1.3.3.4.........3.3.2.3.........3.3.2.4.. .........3.4.4.4.........3.3.4.4.........3.3.3.4.........3.3.4.4 CROSSREFS Sequence in context: A004349 A016092 A028228 * A075907 A062143 A284838 Adjacent sequences:  A165377 A165378 A165379 * A165381 A165382 A165383 KEYWORD nonn AUTHOR R. H. Hardin Sep 17 2009 STATUS approved

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Last modified November 29 04:38 EST 2021. Contains 349416 sequences. (Running on oeis4.)