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a(n) = number of reducible Stern polynomials in range B(1,x) .. B(n,x). (Polynomial B_1(x) = 1 is not included in the count).
4

%I #6 Mar 20 2017 23:21:57

%S 0,0,0,1,1,2,2,3,4,5,5,6,6,7,8,9,9,10,10,11,12,13,13,14,14,15,16,17,

%T 17,18,18,19,20,21,22,23,23,24,25,26,26,27,27,28,29,30,30,31,32,33,34,

%U 35,35,36,36,37,38,39,39,40,40,41,42,43,43,44,44,45,46,47,47,48,48,49,50,51,51,52,52,53,54,55,55,56,57,58,59,60,60,61,61,62,63,64,64

%N a(n) = number of reducible Stern polynomials in range B(1,x) .. B(n,x). (Polynomial B_1(x) = 1 is not included in the count).

%H Antti Karttunen, <a href="/A283993/b283993.txt">Table of n, a(n) for n = 1..10001</a>

%F a(n) = (n-1) - A283992(n).

%o (Scheme) (define (A283993 n) (- n (A283992 n) 1))

%Y Cf. A125184, A260443, A283992, A283994.

%Y Differs from A255572 for the first time at n=65, where a(65) = 43, while A255572(65) = 44.

%K nonn

%O 1,6

%A _Antti Karttunen_, Mar 20 2017