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%I #8 Oct 27 2023 22:00:46
%S 1,2,3,11,127,16195,262286407,68794159432716139,
%T 4732636372053966959311918076028751,
%U 22397847030088134373054567592093233271179679420451463713205492138771
%N a(1) = 1, a(2) = 2, a(n) = sum of products of previous terms taking n-2 at a time.
%C The next term (a(11)) has 135 digits. [From Harvey P. Dale, Feb 29 2012]
%e a(3) = a(1) + a(2) = 3, a(4) = a(1)a(2) + a(2)a(3) + a(3)a(1) = 11, a(5) = 1*2*3 + 1*2*11 + 1*3*11 + 2*3*11 = 127.
%Y Cf. A061902 (lengths of terms).
%K nonn,easy
%O 1,2
%A _Amarnath Murthy_, May 05 2001
%E More terms from _Asher Auel_, May 05 2001. The 11th term has 135 digits.