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%I #19 Jun 26 2022 20:57:20
%S 0,1,16,80,251,612,1269,2354,4021,6449,9844,14427,20458,28203,37972,
%T 50073,64876,82725,104046,129222,158741,193024,232607,277956,329675,
%U 388248,454353,528508,611435,703712,806121,919242,1043953,1180865
%N Number of 2 X 2 matrices M of with all terms in {1,...,n} and permanent(M) >= n.
%C For a guide to related sequences, see A211795.
%F a(n) + A212151(n) = n^4.
%t t = Compile[{{n, _Integer}}, Module[{s = 0},
%t (Do[If[w*x + y*z >= n, s = s + 1],
%t {w, 1, #}, {x, 1, #}, {y, 1, #}, {z, 1, #}] &[n]; s)]];
%t Map[t[#] &, Range[0, 40]] (* A212240 *)
%t (* _Peter J. C. Moses_, Apr 13 2012 *)
%Y Cf. A211795, A212151.
%K nonn
%O 0,3
%A _Clark Kimberling_, May 07 2012
%E Offset changed to 0 by _Georg Fischer_, Feb 03 2022
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