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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A111628 T(2n, 2n-1)/n of A109626.

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%I A111628 #4 Mar 30 2012 18:36:50
%S A111628 1,1,1,1,2,1,2,1,1,1,1,1,2,1,2,1,1,1,2,1,2,1,2,2,2,2,1,2,1,1,1,1,2,1,
%T A111628 2,2,2,2,2,1,2,2,2,2,2,2,2,1,1,2,1,2,2,2,2,2,2,1,2,2,2,2,2,1,1,1,2,1,
%U A111628 1,1,2,1
%N A111628 T(2n, 2n-1)/n of A109626.
%C A111628 A sequence of just 1's and 2's.
%t A111628 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, 2n - 1]/n, {n, 72}]
%Y A111628 Cf. A109626.
%K A111628 nonn
%O A111628 1,5
%A A111628 _Paul D. Hanna_ and _Robert G. Wilson v_, Aug 02 2005