A263507 - OEIS

A263507

Number of (1+1)X(n+1) arrays of permutations of 0..n*2+1 filled by rows with each element moved a city block distance of 0 1 or 2, and rows and columns in increasing lexicographic order.

8, 48, 204, 770, 2687, 8559, 25383, 71498, 193691, 508996, 1306369, 3291584, 8173381, 20060419, 48777993, 117717414, 282365804, 673959638, 1602152316, 3796140809, 8970338435, 21150183227, 49777148466, 116976012851, 274555052038

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OFFSET

1,1

COMMENTS

Row 1 of A263506.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = 6*a(n-1) -12*a(n-2) +9*a(n-3) -4*a(n-4) +2*a(n-5) +10*a(n-6) -12*a(n-7) -a(n-10) +4*a(n-11) -a(n-13)

EXAMPLE

Some solutions for n=4

..0..1..2..4..9....1..2..4..7..8....0..2..4..7..8....0..1..2..8..9