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%I #28 Apr 05 2023 14:35:29
%S 2,1,2,5,10,17,26,37,50,65,82,101,122,145,170,197,226,257,290,325,362,
%T 401,442,485,530,577,626,677,730,785,842,901,962,1025,1090,1157,1226,
%U 1297,1370,1445,1522,1601,1682,1765,1850,1937,2026,2117,2210,2305,2402,2501,2602,2705,2810
%N a(n) = n^2 - 2*n + 2.
%C Competition number of the complete bipartite graph K_{n,n}.
%C Formula given on p. 3 of Sano.
%H Yoshio Sano, <a href="http://arxiv.org/abs/0905.1763">The competition numbers of regular polyhedra</a>, arXiv:0905.1763 [math.CO], 2009.
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (3,-3,1).
%F a(n) = a(n-1)+2*n-3 (with a(0)=2). - _Vincenzo Librandi_, Dec 03 2010
%F a(n) = 3*a(n-1) -3*a(n-2) +a(n-3).
%F G.f.: -(2-5*x+5*x^2)/(x-1)^3.
%F a(n) = A002522(n-1). - _Michel Marcus_, Feb 03 2016
%t Table[n^2-2*n+2, {n,0,5!}] (* _Vladimir Joseph Stephan Orlovsky_, Dec 29 2010 *)
%t LinearRecurrence[{3,-3,1},{2,1,2},60] (* _Harvey P. Dale_, Mar 29 2015 *)
%o (PARI) vector(100,n,n--;n^2 - 2*n + 2)
%Y Cf. A002522, A160450.
%K easy,nonn
%O 0,1
%A _Jonathan Vos Post_, May 14 2009
%E More terms from _Vincenzo Librandi_, Nov 08 2009
%E Sequence corrected by _Joerg Arndt_, Dec 03 2010
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