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%I #4 Mar 30 2012 18:36:50
%S 1,2,1,2,2,2,2,2,2,2,2,2,1,2,1,2,2,2,2,2,2,2,1,2,2,2,1,2,2,2,1,2,1,2,
%T 1,2,1,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,1,2,2,2,1,2,2,2,1,2,2,2,2,2,2,2,
%U 1,2,2,2,2,2,1,2,2,2,2,2
%N T(2n, n)/n of A109626.
%C A sequence of just 1's and 2's.
%t f[n_] := f[n] = Block[{a}, a[0] = 1; a[l_] := a[l] = Block[{k = 1, s = Sum[ a[i]*x^i, {i, 0, l - 1}]}, While[ IntegerQ[ Last[ CoefficientList[ Series[(s + k*x^l)^(1/n), {x, 0, l}], x]]] != True, k++ ]; k]; Table[a[j], {j, 0, 128}]]; g[n_, m_] := f[n][[m]]; Table[ g[2n, n]/n, {n, 80}]
%Y Cf. A109626.
%K nonn
%O 1,2
%A _Paul D. Hanna_ and _Robert G. Wilson v_, Aug 02 2005