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Even-indexed bisection of the first lower diagonal (A111618).
2

%I #4 Mar 30 2012 18:36:50

%S 1,2,3,4,10,6,14,8,9,10,11,12,26,14,30,16,17,18,38,20,42,22,46,48,50,

%T 52,27,56,29,30,31,32,66,34,70,72,74,76,78,40,82,84,86,88,90,92,94,48,

%U 49,100,51,104,106,108,110,112,114,58,118,120,122,124,126,64,65,66,134,68

%N Even-indexed bisection of the first lower diagonal (A111618).

%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, 144}]]; g[n_, m_] := f[n][[m]]; Table[ g[n, n - 1], {n, 2, 144, 2}]

%Y Cf. A111618.

%K nonn

%O 1,2

%A _Paul D. Hanna_ and _Robert G. Wilson v_, Aug 03 2005