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A146198 Number of n X n arrays of squares of integers with every (n-1)X(n-1) subblock summing to 6 and every element equal to at least one neighbor. 1
0, 40, 5606, 41698, 158360, 453388, 1097036, 2364072, 4672136, 8626500, 15071228, 25146736, 40353752, 62623676, 94395340, 138698168, 199241736, 280511732, 387872316, 527674880, 707373208 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,2

LINKS

Table of n, a(n) for n=3..23.

FORMULA

Empirical (for n>=7): a(n) = 80*n^6/9 - 401*n^5/3 + 10112*n^4/9 - 5809*n^3 + 145814*n^2/9 - 64942*n/3 + 11612. - Vaclav Kotesovec, Nov 30 2012

CROSSREFS

Sequence in context: A270053 A123810 A275655 * A159376 A196706 A196855

Adjacent sequences:  A146195 A146196 A146197 * A146199 A146200 A146201

KEYWORD

nonn

AUTHOR

R. H. Hardin Apr 14 2009

STATUS

approved

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Last modified September 20 13:07 EDT 2020. Contains 337264 sequences. (Running on oeis4.)