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 A146125 Number of n X n arrays of squares of integers with every (n-1) X (n-1) subblock summing to 5 and every element equal to at least one neighbor. 1
 0, 93, 2046, 8675, 24622, 56389, 112078, 201457, 335974, 528757, 794614, 1150033, 1613182, 2203909, 2943742, 3855889, 4965238, 6298357, 7883494, 9750577, 11931214, 14458693, 17367982, 20695729, 24480262 (list; graph; refs; listen; history; text; internal format)
 OFFSET 3,2 LINKS Table of n, a(n) for n=3..27. FORMULA Empirical (for n>=7): a(n) = 70*n^4 - 752*n^3 + 3059*n^2 - 5680*n + 4357. - Vaclav Kotesovec, Nov 30 2012 Conjectures from Colin Barker, Mar 23 2018: (Start) G.f.: x^4*(93 + 1581*x - 625*x^2 + 777*x^3 + 34*x^4 - 260*x^5 + 66*x^6 + 14*x^7) / (1 - x)^5. a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n>11. (End) CROSSREFS Sequence in context: A264556 A250373 A250374 * A353002 A017809 A017756 Adjacent sequences: A146122 A146123 A146124 * A146126 A146127 A146128 KEYWORD nonn AUTHOR R. H. Hardin, Apr 14 2009 STATUS approved

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Last modified December 5 19:33 EST 2023. Contains 367593 sequences. (Running on oeis4.)