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a(n) = the largest coefficient in Stern polynomial B(n,t).
7

%I #8 Oct 13 2016 10:30:28

%S 0,1,1,1,1,2,1,1,1,2,2,3,1,2,1,1,1,2,2,3,2,4,3,3,1,3,2,3,1,2,1,1,1,2,

%T 2,3,2,5,3,4,2,4,4,6,3,5,3,3,1,3,3,5,2,5,3,4,1,3,2,3,1,2,1,1,1,2,2,3,

%U 2,5,3,4,2,6,5,8,3,7,4,4,2,4,4,8,4,10,6,7,3,6,5,8,3,5,3,3,1,3,3,5,3,7,5,6,2,6,5,8,3,7,4,4,1,4,3,5,2,5,3,4,1

%N a(n) = the largest coefficient in Stern polynomial B(n,t).

%C a(n) = gives the largest term on row n of table A125184.

%H Antti Karttunen, <a href="/A277315/b277315.txt">Table of n, a(n) for n = 0..8192</a>

%F a(n) = A051903(A260443(n)).

%F a(2n) = a(n).

%o (Scheme)

%o (define (A277315 n) (A051903 (A260443 n)))

%o ;; Or as a standalone program:

%o (define (A277315 n) (reduce max 0 (A260443as_coeff_list n)))

%o (definec (A260443as_coeff_list n) (cond ((zero? n) (list)) ((= 1 n) (list 1)) ((even? n) (cons 0 (A260443as_coeff_list (/ n 2)))) (else (add_two_lists (A260443as_coeff_list (/ (- n 1) 2)) (A260443as_coeff_list (/ (+ n 1) 2))))))

%o (define (add_two_lists nums1 nums2) (let ((len1 (length nums1)) (len2 (length nums2))) (cond ((< len1 len2) (add_two_lists nums2 nums1)) (else (map + nums1 (append nums2 (make-list (- len1 len2) 0)))))))

%Y Cf. A051903, A125184, A260443.

%K nonn

%O 0,6

%A _Antti Karttunen_, Oct 10 2016