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A182756 Numbers k > 1 such that are sequences B_k of type: {b(1) = 1, b(2) = k, for n >= 3; b(n) = the smallest number h > b(n-1) such that [[b(n-2) + b(n-1)] * [b(n-2) + h] * [b(n-1) + h]] / [b(n-2) * b(n-1) * h] is integer}. 5

%I #9 Apr 30 2014 01:27:36

%S 2,3,6,14,21,35,77,90,234,286,611

%N Numbers k > 1 such that are sequences B_k of type: {b(1) = 1, b(2) = k, for n >= 3; b(n) = the smallest number h > b(n-1) such that [[b(n-2) + b(n-1)] * [b(n-2) + h] * [b(n-1) + h]] / [b(n-2) * b(n-1) * h] is integer}.

%C With 1 complement of A182757.

%C Is this a union/superset of A032908 and A101879? -- _Ralf Stephan_, Nov 29 2010

%e For n =1; a(n) = 2; B_2 = A038754(n): 1, 2, 3, 6, 9, 18, 27, 54, 81, 162, 243, 486, …

%e For n =2; a(n) = 3; B_3 = A182751(n): 1, 3, 6, 9, 18, 27, 54, 81, 162, 243, 486, …

%e For n =3; a(n) = 6; B_6 = A182752(n): 1, 6, 14, 84, 196, 1176, 2744, 16464, 38416, …

%e For n =4; a(n) = 14; B_14 = A182753(n): 1, 14, 35, 490, 1225, 17150, 42875, …

%e For n =5; a(n) = 21; B_21 = A182754(n): 1, 21, 77, 1617, 5929, 124509, 456533, …

%e For n =6; a(n) = 35; B_35 = A182755(n): 1, 35, 90, 3150, 8100, 283500, 729000, …

%Y Cf. A182751, A182752, A182753, A182754, A182755, A182757, A038754.

%K nonn,more

%O 1,1

%A _Jaroslav Krizek_, Nov 27 2010

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