A292588 - OEIS

%I #7 Sep 26 2017 20:28:31

%S 1,1,2,3,2,2,4,6,3,2,7,5,7,4,4,10,7,3,11,5,2,7,16,9,3,7,9,8,16,4,22,

%T 15,4,7,7,21,22,11,11,9,22,2,29,12,5,16,37,14,3,3,11,12,37,9,4,13,7,

%U 16,46,8,46,22,8,28,4,4,56,12,11,7,67,36,67,22,5,17,7,11,79,14,10,22,92,5,11,29,22,18,92,5,7,23,16,37,16,20,92,3,122,21,92,11

%N Compound filter: a(n) = P(A292582(n), A292583(n)), where P(n,k) is sequence A000027 used as a pairing function.

%C A filter constructed from the runlengths of numbers of the form 4k+0 and the runlengths of numbers of the form 4k+3 encountered in trajectories of A005940-tree.

%H Antti Karttunen, <a href="/A292588/b292588.txt">Table of n, a(n) for n = 1..16384</a>

%H <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>

%F a(n) = (1/2)*(2 + ((A292582(n) + A292583(n))^2) - A292582(n) - 3*A292583(n)).

%Y Cf. A000027, A292582, A292583, A292584, A292587.

%K nonn

%O 1,3

%A _Antti Karttunen_, Sep 26 2017