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A098144 a(n) = smallest number greater than a(n-1) having a largest proper divisor that is greater than and coprime to a(n-1); a(1) = 1. 0

%I

%S 1,4,9,10,21,22,39,40,63,64,99,100,153,154,237,238,363,364,549,550,

%T 831,832,1251,1252,1881,1882,2829,2830,4251,4252,6381,6382,9579,9580,

%U 14373,14374,21567,21568,32355,32356,48537,48538,72813,72814,109227,109228

%N a(n) = smallest number greater than a(n-1) having a largest proper divisor that is greater than and coprime to a(n-1); a(1) = 1.

%C A032742(a(n+1))>A032742(a(n)) and GCD(A032742(a(n+1)), A032742(a(n)))=1;

%C for n>1: a(2*n) = a(2*n-1) + 1,

%C a(2*n+1) = 3*(a(2*n)/2 + 2 - 0^(a(2*n) mod 4)).

%K nonn

%O 1,2

%A _Reinhard Zumkeller_, Sep 28 2004

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Last modified October 19 23:44 EDT 2021. Contains 348095 sequences. (Running on oeis4.)