A265990 - OEIS

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A265990

Number of nX7 integer arrays with each element equal to the number of horizontal and antidiagonal neighbors not equal to itself.

1, 7, 9, 24, 59, 137, 422, 865, 2777, 5666, 16753, 35213, 94722, 205921, 510225, 1143426, 2648225, 6090517, 13350146, 31380721, 65741593, 157403330, 317579601, 772359709, 1509772802, 3721329089, 7080934945, 17656526082, 32827306561

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

COMMENTS

Column 7 of A265991.

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +16*a(n-2) -15*a(n-3) -97*a(n-4) +84*a(n-5) +268*a(n-6) -208*a(n-7) -304*a(n-8) +192*a(n-9) +64*a(n-10) for n>15

EXAMPLE

Some solutions for n=4

..1..3..1..1..3..1..1....1..3..1..1..3..1..1....1..3..2..2..1..1..2